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[GMCnet] Transmission problems [message #302270] Sat, 18 June 2016 16:04 Go to next message
RicksGMC is currently offline  RicksGMC   United States
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Registered: May 2012
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Senior Member
I need some urgent advice/ help with a transmission problem that just started, we are supposed to be leaving for Branson on Thursday.

I took the GMC out for a test drive today in preparation for our trip to Branson. It ran great for 20 miles or so then I pulled onto the interstate with an immediate uphill incline and had to get on the gas to accelerate enough for the merge causing the transmission to downshift. After that it would only go into 2nd gear and never into 3rd, I made it back home by taking side streets. A few times it was having a hard time shifting out of 1st.
I checked fluid level and added a pint, took it for another drive and it's still not shifting.
I'm looking for any suggestions of things I can check that might be causing this that I can resolve so we can still go to Branson.
Thanks in advance!

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302272 is a reply to message #302270] Sat, 18 June 2016 16:23 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
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Senior Member
Check the vacuum line to the modulator, be sure it's not cracked or loose. Next call Manny.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Transmission problems [message #302278 is a reply to message #302270] Sat, 18 June 2016 17:05 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Check your vacuum line to trans fron intake.


On Sat, Jun 18, 2016 at 2:04 PM, Rick Drummond wrote:

> I need some urgent advice/ help with a transmission problem that just
> started, we are supposed to be leaving for Branson on Thursday.
>
> I took the GMC out for a test drive today in preparation for our trip to
> Branson. It ran great for 20 miles or so then I pulled onto the interstate
> with an immediate uphill incline and had to get on the gas to accelerate
> enough for the merge causing the transmission to downshift. After that it
> would only go into 2nd gear and never into 3rd, I made it back home by
> taking side streets. A few times it was having a hard time shifting out of
> 1st.
> I checked fluid level and added a pint, took it for another drive and it's
> still not shifting.
> I'm looking for any suggestions of things I can check that might be
> causing this that I can resolve so we can still go to Branson.
> Thanks in advance!
>
> Rick
>
> Rick&Tammy Drummond
> Prior Lake MN
> '74 (re)Painted Desert
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Transmission problems [message #302279 is a reply to message #302278] Sat, 18 June 2016 17:06 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Call me 800-752-7502


On Sat, Jun 18, 2016 at 3:05 PM, Jim Kanomata wrote:

> Check your vacuum line to trans fron intake.
>
>
> On Sat, Jun 18, 2016 at 2:04 PM, Rick Drummond
> wrote:
>
>> I need some urgent advice/ help with a transmission problem that just
>> started, we are supposed to be leaving for Branson on Thursday.
>>
>> I took the GMC out for a test drive today in preparation for our trip to
>> Branson. It ran great for 20 miles or so then I pulled onto the interstate
>> with an immediate uphill incline and had to get on the gas to accelerate
>> enough for the merge causing the transmission to downshift. After that it
>> would only go into 2nd gear and never into 3rd, I made it back home by
>> taking side streets. A few times it was having a hard time shifting out of
>> 1st.
>> I checked fluid level and added a pint, took it for another drive and
>> it's still not shifting.
>> I'm looking for any suggestions of things I can check that might be
>> causing this that I can resolve so we can still go to Branson.
>> Thanks in advance!
>>
>> Rick
>>
>> Rick&Tammy Drummond
>> Prior Lake MN
>> '74 (re)Painted Desert
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Transmission problems [message #302282 is a reply to message #302278] Sat, 18 June 2016 18:02 Go to previous messageGo to next message
RicksGMC is currently offline  RicksGMC   United States
Messages: 145
Registered: May 2012
Karma: 0
Senior Member
I checked the vacuum line and it appears connected and intact. I put a vacuum tester on the line to the transmission modulator and it holds vacuum though I'm not sure if the modulator is actually functioning or not.
I also followed the procedure to test the throttle kick down solenoid, the manual states I should hear a click from the modulator when pedal is depressed but mine does not make any sound (that I can hear).

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 18, 2016, at 5:05 PM, Jim Kanomata wrote:
>
> Check your vacuum line to trans fron intake.
>
>
>> On Sat, Jun 18, 2016 at 2:04 PM, Rick Drummond wrote:
>>
>> I need some urgent advice/ help with a transmission problem that just
>> started, we are supposed to be leaving for Branson on Thursday.
>>
>> I took the GMC out for a test drive today in preparation for our trip to
>> Branson. It ran great for 20 miles or so then I pulled onto the interstate
>> with an immediate uphill incline and had to get on the gas to accelerate
>> enough for the merge causing the transmission to downshift. After that it
>> would only go into 2nd gear and never into 3rd, I made it back home by
>> taking side streets. A few times it was having a hard time shifting out of
>> 1st.
>> I checked fluid level and added a pint, took it for another drive and it's
>> still not shifting.
>> I'm looking for any suggestions of things I can check that might be
>> causing this that I can resolve so we can still go to Branson.
>> Thanks in advance!
>>
>> Rick
>>
>> Rick&Tammy Drummond
>> Prior Lake MN
>> '74 (re)Painted Desert
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302284 is a reply to message #302282] Sat, 18 June 2016 19:26 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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Registered: April 2006
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Senior Member
Sir, the switch is under the dash on top of the acceraletor pedal. Maybe unplug it and see if it unclicks. The activator wire is usually ran with the vacuum line to trans. Plugs in side. Does your speedo still work?


RicksGMC wrote on Sat, 18 June 2016 19:02
I checked the vacuum line and it appears connected and intact. I put a vacuum tester on the line to the transmission modulator and it holds vacuum though I'm not sure if the modulator is actually functioning or not.
I also followed the procedure to test the throttle kick down solenoid, the manual states I should hear a click from the modulator when pedal is depressed but mine does not make any sound (that I can hear).

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 18, 2016, at 5:05 PM, Jim Kanomata wrote:
>
> Check your vacuum line to trans fron intake.
>
>
>> On Sat, Jun 18, 2016 at 2:04 PM, Rick Drummond wrote:
>>
>> I need some urgent advice/ help with a transmission problem that just
>> started, we are supposed to be leaving for Branson on Thursday.
>>
>> I took the GMC out for a test drive today in preparation for our trip to
>> Branson. It ran great for 20 miles or so then I pulled onto the interstate
>> with an immediate uphill incline and had to get on the gas to accelerate
>> enough for the merge causing the transmission to downshift. After that it
>> would only go into 2nd gear and never into 3rd, I made it back home by
>> taking side streets. A few times it was having a hard time shifting out of
>> 1st.
>> I checked fluid level and added a pint, took it for another drive and it's
>> still not shifting.
>> I'm looking for any suggestions of things I can check that might be
>> causing this that I can resolve so we can still go to Branson.
>> Thanks in advance!
>>
>> Rick
>>
>> Rick&Tammy Drummond
>> Prior Lake MN
>> '74 (re)Painted Desert
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Transmission problems [message #302286 is a reply to message #302284] Sat, 18 June 2016 19:44 Go to previous messageGo to next message
RicksGMC is currently offline  RicksGMC   United States
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Registered: May 2012
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Senior Member
I used a volt meter and tested the switch on the accelerator pedal and it tested ok.
The speedometer is functioning properly also.

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 18, 2016, at 7:26 PM, Charles Boyd wrote:
>
> Sir, the switch is under the dash on top of the acceraletor pedal. Maybe unplug it and see if it unclicks. The activator wire is usually ran with
> the vacuum line to trans. Plugs in side. Does your speedo still work?
>
>
> RicksGMC wrote on Sat, 18 June 2016 19:02
>> I checked the vacuum line and it appears connected and intact. I put a vacuum tester on the line to the transmission modulator and it holds vacuum
>> though I'm not sure if the modulator is actually functioning or not.
>> I also followed the procedure to test the throttle kick down solenoid, the manual states I should hear a click from the modulator when pedal is
>> depressed but mine does not make any sound (that I can hear).
>>
>> Rick
>>
>> Rick&Tammy Drummond
>> Prior Lake MN
>> '74 (re)Painted Desert
>>
>>> On Jun 18, 2016, at 5:05 PM, Jim Kanomata wrote:
>>>
>>> Check your vacuum line to trans fron intake.
>>>
>>>
>>>> On Sat, Jun 18, 2016 at 2:04 PM, Rick Drummond wrote:
>>>>
>>>> I need some urgent advice/ help with a transmission problem that just
>>>> started, we are supposed to be leaving for Branson on Thursday.
>>>>
>>>> I took the GMC out for a test drive today in preparation for our trip to
>>>> Branson. It ran great for 20 miles or so then I pulled onto the interstate
>>>> with an immediate uphill incline and had to get on the gas to accelerate
>>>> enough for the merge causing the transmission to downshift. After that it
>>>> would only go into 2nd gear and never into 3rd, I made it back home by
>>>> taking side streets. A few times it was having a hard time shifting out of
>>>> 1st.
>>>> I checked fluid level and added a pint, took it for another drive and it's
>>>> still not shifting.
>>>> I'm looking for any suggestions of things I can check that might be
>>>> causing this that I can resolve so we can still go to Branson.
>>>> Thanks in advance!
>>>>
>>>> Rick
>>>>
>>>> Rick&Tammy Drummond
>>>> Prior Lake MN
>>>> '74 (re)Painted Desert
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>>
>>>
>>> --
>>> Jim Kanomata
>>> Applied/GMC, Fremont,CA
>>> jimk@appliedairfilters.com
>>> http://www.appliedgmc.com
>>> 1-800-752-7502
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
>
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302290 is a reply to message #302270] Sat, 18 June 2016 21:41 Go to previous messageGo to next message
KB is currently offline  KB   United States
Messages: 1262
Registered: September 2009
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Senior Member
we recently had the same problem with no 3rd gear. Turned out to be
the governor. It can get gummed up inside so it doesn't move freely. The fix
is to pull the governor (easy to do), drive out the little pin that holds
the plastic gear on, and slide the inner shaft out the bottom so you can clean
everything up. Ours was so stuck it was difficult to get the shaft out; it
should normally slip right out when the plastic gear is removed.

When you put it back together, be sure to stake the little roll pin
so it can't move. Otherwise the pin can go sideways and make it
really difficult to get the governor out (or worse).

Karen
1975 26'

Re: [GMCnet] Transmission problems [message #302296 is a reply to message #302270] Sat, 18 June 2016 23:39 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Since it happened right after you floored it, I strongly suspect the kickdown switch or the kick down solenoid. Unplug the wire from the trans and see if the problem goes away. If it does, you can drive it that way and not hurt anything. You just will not have any passing gear. You can still pull it down manually with the gear shift.

If unplugging it does not change the symptoms, it still could be the kickdown solenoid in the trans. It also can be a vacuum leak anywhere in the rubber and steel line from the intake to the modulator. Finally as suggested previously it could be a sticking governor.

Chuck Boyd asked this before.

Does the speedometer work?


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Transmission problems [message #302310 is a reply to message #302296] Sun, 19 June 2016 13:08 Go to previous messageGo to next message
RicksGMC is currently offline  RicksGMC   United States
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Registered: May 2012
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Senior Member
To eliminate causes I pulled and inspected the governor, which appeared just fine; I re-checked the vacuum line and fittings to the modulator, using a hand vac pump I pulled vac on the modulator and steel line and it held pressure. I used a volt meter and checked the kick-down switch on the accelerator pedal and it appears to be functioning properly which leaves me with the kick-down solenoid.
I have the orange wire to the solenoid disconnected right now and took another test drive, it appears to be shifting properly again; so question is did something I touch resolve it or could it be temperature related?
The other question I have is how to know for sure it's shifting? The tranny shifts so smooth I don't actually hear it, when it was acting up yesterday at 55-65mph the rpm's are about 3500 today at 55-65mph rpm's are 2300-2500 (3.70 final drive) does that sound correct?


Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 18, 2016, at 11:39 PM, Ken Burton wrote:
>
> Since it happened right after you floored it, I strongly suspect the kickdown switch or the kick down solenoid. Unplug the wire from the trans and
> see if the problem goes away. If it does, you can drive it that way and not hurt anything. You just will not have any passing gear. You can still
> pull it down manually with the gear shift.
>
> If unplugging it does not change the symptoms, it still could be the kickdown solenoid in the trans. It also can be a vacuum leak anywhere in the
> rubber and steel line from the intake to the modulator. Finally as suggested previously it could be a sticking governor.
>
> Chuck Boyd asked this before.
>
> Does the speedometer work?
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302311 is a reply to message #302310] Sun, 19 June 2016 13:15 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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RicksGMC wrote on Sun, 19 June 2016 13:08
To eliminate causes I pulled and inspected the governor, which appeared just fine; I re-checked the vacuum line and fittings to the modulator, using a hand vac pump I pulled vac on the modulator and steel line and it held pressure. I used a volt meter and checked the kick-down switch on the accelerator pedal and it appears to be functioning properly which leaves me with the kick-down solenoid.
I have the orange wire to the solenoid disconnected right now and took another test drive, it appears to be shifting properly again; so question is did something I touch resolve it or could it be temperature related?
The other question I have is how to know for sure it's shifting? The tranny shifts so smooth I don't actually hear it, when it was acting up yesterday at 55-65mph the rpm's are about 3500 today at 55-65mph rpm's are 2300-2500 (3.70 final drive) does that sound correct?

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert
The RPMs at speed indicate you have a 3.07 final drive. If you reconnect the kickdown solenoid and it stops shifting, there's your culprit. If it continues to shift correctly with the kickdown solenoid reconnected, that would indicate a connection corrosion issue that you cleared when disconnecting and reconnecting.
Re: [GMCnet] Transmission problems [message #302315 is a reply to message #302310] Sun, 19 June 2016 13:26 Go to previous messageGo to next message
Rob is currently offline  Rob   United States
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Registered: November 2013
Location: Victoria, BC
Karma: 3
Senior Member
See this link for "Engine RPM vs Speed" (in third):

http://gdurl.com/ion9

(snatched from someone's GMC info - thanks!!)

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

On 2016-06-19, at 11:08 AM, Rick Drummond wrote:

> To eliminate causes I pulled and inspected the governor, which appeared just fine; I re-checked the vacuum line and fittings to the modulator, using a hand vac pump I pulled vac on the modulator and steel line and it held pressure. I used a volt meter and checked the kick-down switch on the accelerator pedal and it appears to be functioning properly which leaves me with the kick-down solenoid.
> I have the orange wire to the solenoid disconnected right now and took another test drive, it appears to be shifting properly again; so question is did something I touch resolve it or could it be temperature related?
> The other question I have is how to know for sure it's shifting? The tranny shifts so smooth I don't actually hear it, when it was acting up yesterday at 55-65mph the rpm's are about 3500 today at 55-65mph rpm's are 2300-2500 (3.70 final drive) does that sound correct?
>
>
> Rick
>
> Rick&Tammy Drummond
> Prior Lake MN
> '74 (re)Painted Desert
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Rob - Victoria, BC - 76 Royale - Rear Twins/Dry Bath
Re: [GMCnet] Transmission problems [message #302325 is a reply to message #302310] Sun, 19 June 2016 14:48 Go to previous messageGo to next message
KB is currently offline  KB   United States
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Senior Member
RicksGMC wrote on Sun, 19 June 2016 11:08
To eliminate causes I pulled and inspected the governor, which appeared just fine


I thought ours appeared fine too, after carefully checking it, observing the gap, etc.
It wasn't until I removed the plastic gear to clean the insides that I noticed the shaft wouldn't slide out. Once I got it apart, I found a fine sludge that was keeping it from moving as easily as it should.

I did this because our spare governor fixed the problem (so there was clearly something wrong), and I'd learned from Manny that
he disassembles and cleans all the governors that pass his way, and it usually fixes them.

Karen
1975 26'



Re: [GMCnet] Transmission problems [message #302345 is a reply to message #302311] Sun, 19 June 2016 16:54 Go to previous messageGo to next message
RicksGMC is currently offline  RicksGMC   United States
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Senior Member
I reconnected the wire to the kick-down solenoid and drove it and now it appears to be shifting properly again. I'll go with the hope that I touched and corrected whatever was causing it... I plan on driving it as much as I can this week before we leave just to make sure.
Other than RPM's is there any indication that the transmission is actually shifting thru all 3 gears?

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 19, 2016, at 1:15 PM, A. wrote:
>
> RicksGMC wrote on Sun, 19 June 2016 13:08
>> To eliminate causes I pulled and inspected the governor, which appeared just fine; I re-checked the vacuum line and fittings to the modulator,
>> using a hand vac pump I pulled vac on the modulator and steel line and it held pressure. I used a volt meter and checked the kick-down switch on the
>> accelerator pedal and it appears to be functioning properly which leaves me with the kick-down solenoid.
>> I have the orange wire to the solenoid disconnected right now and took another test drive, it appears to be shifting properly again; so question
>> is did something I touch resolve it or could it be temperature related?
>> The other question I have is how to know for sure it's shifting? The tranny shifts so smooth I don't actually hear it, when it was acting up
>> yesterday at 55-65mph the rpm's are about 3500 today at 55-65mph rpm's are 2300-2500 (3.70 final drive) does that sound correct?
>>
>> Rick
>>
>> Rick&Tammy Drummond
>> Prior Lake MN
>> '74 (re)Painted Desert
> The RPMs at speed indicate you have a 3.07 final drive. If you reconnect the kickdown solenoid and it stops shifting, there's your culprit. If it
> continues to shift correctly with the kickdown solenoid reconnected, that would indicate a connection corrosion issue that you cleared when
> disconnecting and reconnecting.
> --
> 73 23' Sequoia 4 Sale
> 73 23' CanyonLands Parts Unit 4 Sale
> Upper Alabama
> "Posting on the GMCnet seems to always result in a cacophony of responses which only tend to cloud the solution rather than move you closer to it."
> Jim Miller
>
> _______________________________________________
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302352 is a reply to message #302270] Sun, 19 June 2016 17:47 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Location: Braselton ga
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Senior Member
Have the copilot watch the tach as you accelerate with a fixed throttle position. You'll see two instances where it drops perceptibly. The 1-2 shift is at a fairly low speed unless you're really standing on it. However, your reported RPM and road speed correspond to my 3.07 coach.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Transmission problems [message #302353 is a reply to message #302270] Sun, 19 June 2016 17:52 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Location: St. Cloud, MN
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Senior Member
Rick,

You will know it is not in 3rd gear if you drive 1 exit down i-35.

You will also not be able to go very fast stuck in 1st.
Starting on a hill from a dead start, you will know if it is not starting in 3rd. Pay attention. You can count the shifts even so suttle.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] Transmission problems [message #302364 is a reply to message #302353] Sun, 19 June 2016 18:29 Go to previous messageGo to next message
RicksGMC is currently offline  RicksGMC   United States
Messages: 145
Registered: May 2012
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Senior Member
I-35 will be my next test drive, it broke on I-35 so that should be a valid test! ;)


Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 19, 2016, at 5:52 PM, Jon Roche wrote:
>
> Rick,
>
> You will know it is not in 3rd gear if you drive 1 exit down i-35.
>
> You will also not be able to go very fast stuck in 1st.
> Starting on a hill from a dead start, you will know if it is not starting in 3rd. Pay attention. You can count the shifts even so suttle.
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302376 is a reply to message #302352] Sun, 19 June 2016 19:52 Go to previous messageGo to next message
RicksGMC is currently offline  RicksGMC   United States
Messages: 145
Registered: May 2012
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Senior Member
I'll try the copilot watching the tach trick on the next drive.
I was a little vague with my rpm #s, so I rechecked:
50mph is 2200-2300
60mph is 2800-2900
According to PO the coach has a 3.70 final drive from Jim K.

Thanks to everyone for your help and suggestions!

Rick

Rick&Tammy Drummond
Prior Lake MN
'74 (re)Painted Desert

> On Jun 19, 2016, at 5:47 PM, Johnny Bridges via Gmclist wrote:
>
> Have the copilot watch the tach as you accelerate with a fixed throttle position. You'll see two instances where it drops perceptibly. The 1-2 shift
> is at a fairly low speed unless you're really standing on it. However, your reported RPM and road speed correspond to my 3.07 coach.
>
> --johnny
>
> --
> '76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
>
> "Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
>
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Rick Rick&Tammy Drummond Prior Lake MN '74 (re)Painted Desert
Re: [GMCnet] Transmission problems [message #302387 is a reply to message #302310] Sun, 19 June 2016 22:58 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Registered: January 2004
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Rick — one way to tell if it shifted into high is to use the shift lever to downshift to second and check the rams. Then shift back into drive and it should run at a lower rpm if its has shifted.

Emery Stora

> On Jun 19, 2016, at 12:08 PM, Rick Drummond wrote:
>
> To eliminate causes I pulled and inspected the governor, which appeared just fine; I re-checked the vacuum line and fittings to the modulator, using a hand vac pump I pulled vac on the modulator and steel line and it held pressure. I used a volt meter and checked the kick-down switch on the accelerator pedal and it appears to be functioning properly which leaves me with the kick-down solenoid.
> I have the orange wire to the solenoid disconnected right now and took another test drive, it appears to be shifting properly again; so question is did something I touch resolve it or could it be temperature related?
> The other question I have is how to know for sure it's shifting? The tranny shifts so smooth I don't actually hear it, when it was acting up yesterday at 55-65mph the rpm's are about 3500 today at 55-65mph rpm's are 2300-2500 (3.70 final drive) does that sound correct?
>
>
> Rick
>
> Rick&Tammy Drummond
> Prior Lake MN
> '74 (re)Painted Desert
>
>> On Jun 18, 2016, at 11:39 PM, Ken Burton wrote:
>>
>> Since it happened right after you floored it, I strongly suspect the kickdown switch or the kick down solenoid. Unplug the wire from the trans and
>> see if the problem goes away. If it does, you can drive it that way and not hurt anything. You just will not have any passing gear. You can still
>> pull it down manually with the gear shift.
>>
>> If unplugging it does not change the symptoms, it still could be the kickdown solenoid in the trans. It also can be a vacuum leak anywhere in the
>> rubber and steel line from the intake to the modulator. Finally as suggested previously it could be a sticking governor.
>>
>> Chuck Boyd asked this before.
>>
>> Does the speedometer work?
>> --
>> Ken Burton - N9KB
>> 76 Palm Beach
>> Hebron, Indiana
>>
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Re: [GMCnet] Transmission problems [message #302400 is a reply to message #302270] Mon, 20 June 2016 08:16 Go to previous message
jhbridges is currently offline  jhbridges   United States
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Registered: May 2011
Location: Braselton ga
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Those revised RPM numbers correspond to my 3.70 coach.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
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