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3rd gear loss of power [message #269797] Fri, 16 January 2015 18:09 Go to next message
KB is currently offline  KB   United States
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right after pulling back onto the freeway after the shattered window episode today,
we suddenly suffered a loss of power in 3rd gear. It was like it was somehow shifting from 2nd to neutral instead of 3rd.
Since we were already pretty shaken up by the broken window, this was really not helpful.
We pulled over to check the tranny fluid level, which was fine, and then limped home the remaining 30 miles or so in 2nd gear.

So, any thoughts on what to check? I'm thinking vacuum modulator line, or maybe the shift linkage.
Other ideas?

thanks,
Karen
1975 26'
Re: [GMCnet] 3rd gear loss of power [message #269799 is a reply to message #269797] Fri, 16 January 2015 18:18 Go to previous messageGo to next message
mercdave is currently offline  mercdave   
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Redacted
----- Original Message -----


Dave L
Lynnwood, Wa.

1976 GMC 26' Edgemonte Rear Twin
1973 GMC 23' Rear-Ended, Totaled

[Updated on: Fri, 16 January 2015 18:28]

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Re: [GMCnet] 3rd gear loss of power [message #269801 is a reply to message #269799] Fri, 16 January 2015 18:20 Go to previous messageGo to next message
mercdave is currently offline  mercdave   
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Sorry folks I replied to the wrong message here.

----- Original Message -----


Dave L
Lynnwood, Wa.

1976 GMC 26' Edgemonte Rear Twin
1973 GMC 23' Rear-Ended, Totaled

[Updated on: Fri, 16 January 2015 18:47]

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Re: 3rd gear loss of power [message #269803 is a reply to message #269797] Fri, 16 January 2015 18:42 Go to previous messageGo to next message
KB is currently offline  KB   United States
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our sense was that it was dropping into neutral instead of 3rd gear; Loss of power and sudden rpm increase.
I just replayed the EBL log and can see that the RPM's do increase dramatically during the trouble spots -- revs up to 3000 RPM or so.

thanks,
Karen
1975 26'

Re: [GMCnet] 3rd gear loss of power [message #269804 is a reply to message #269803] Fri, 16 January 2015 18:44 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   
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Can you think of any reason why this might be related to the shattered window? Could there have been some debris on the road that hit the vacuum lines, or something?

Larry Davick
Fremont, California
A Mystery Machine
'76 (ish) Palm Beach
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: 3rd gear loss of power [message #269805 is a reply to message #269797] Fri, 16 January 2015 19:00 Go to previous messageGo to next message
bobby5832708 is currently offline  bobby5832708   United States
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Did you lose reverse too? Or does the coach shudder when you gas it a bit in reverse?

Bob Heller
2017 Winnebago 29VE
Winter Springs FL
Re: 3rd gear loss of power [message #269808 is a reply to message #269805] Fri, 16 January 2015 19:25 Go to previous messageGo to next message
KB is currently offline  KB   United States
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bobby5832708 wrote on Fri, 16 January 2015 17:00
Did you lose reverse too? Or does the coach shudder when you gas it a bit in reverse?


we never tried reverse; too intent on getting home. So, I went out just now and tried it in the driveway and it was kinda funky. It went into reverse OK, but then when I shifted to drive, nothing. No drive, no S, no L. back to reverse, nothing there either. Cycled it around and back to drive and it was OK, shifted it up and down a few more times but couldn't get it to misbehave again.
Whatever the problem, it seems to be intermittent. Sad

We've often had trouble getting it to go into gear the first time when it's been sitting a while (torque converter drainback we're guessing), but it's always worked after that. The fluid level is for sure not low; I'm paranoid about checking the level every trip.

thanks
Karen
1975 26'



Re: 3rd gear loss of power [message #269809 is a reply to message #269797] Fri, 16 January 2015 19:28 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Karen, I hate to say it but it sure sounds like the same tranny problem I had. Talk to Manny. Third gear and Reverse use the same clutch pack and if it's toast, it will slip in third and jerk in reverse.

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: 3rd gear loss of power [message #269810 is a reply to message #269797] Fri, 16 January 2015 19:34 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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KB wrote on Fri, 16 January 2015 16:09


So, any thoughts on what to check? I'm thinking vacuum modulator line, or maybe the shift linkage.
Other ideas?

thanks,
Karen
1975 26'


Wow. Not your day!

When the hose to the modulator was leaking the shift to third was delayed on our coach. At 55 (we have a 3.21) the upshift was forced by the governor. The shift was good and solid, because of the high RPMs. I had mine be in neutral when it was supposed to be in 3rd, but if you hit the gas it revved back to 2nd gear ratios. That was only remedied by a visit to Manny's.

Shifting to neutral is not good, I don't think.Hope it is not something big.



'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: 3rd gear loss of power [message #269813 is a reply to message #269809] Fri, 16 January 2015 20:00 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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kerry pinkerton wrote on Fri, 16 January 2015 19:28
Karen, I hate to say it but it sure sounds like the same tranny problem I had. Talk to Manny. Third gear and Reverse use the same clutch pack and if it's toast, it will slip in third and jerk in reverse.
d

I had the same failure as Kerry a few years back. I drove it home in second. After I arrived, I found that reverse also had a problem. I pulled the dip stick. I found ground up clutch stuff on one side of it only. The solution was a rebuilt Manny Transmission. It just quit without any warning.

Sorry...


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: 3rd gear loss of power [message #269817 is a reply to message #269813] Fri, 16 January 2015 20:19 Go to previous messageGo to next message
KB is currently offline  KB   United States
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guess if I can't find anything else obviously wrong, I'll drain the fluid and look for debris.
Luckily I have a beautiful ragusa tranny pan with a drain bung, so it's an easy job. One of the better upgrades, imho.

I would think that a ruined clutch would be more consistently bad. This is weird because it works OK sometimes, then not,
and it's not limited to just 3rd and/or reverse -- it also wouldn't go into D or S or L, but then it would...

Sounds like I'll be bothering poor Manny again sometime soon...

thanks,
Karen
1975 26'
Re: [GMCnet] 3rd gear loss of power [message #269821 is a reply to message #269804] Fri, 16 January 2015 20:22 Go to previous messageGo to next message
KB is currently offline  KB   United States
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ljdavick wrote on Fri, 16 January 2015 16:44
Can you think of any reason why this might be related to the shattered window? Could there have been some debris on the road that hit the vacuum lines, or something?



it's possible; I'll get under there in daylight and see if there's anything obviously amiss.

thanks
Karen
1975 26'

Re: 3rd gear loss of power [message #269822 is a reply to message #269797] Fri, 16 January 2015 20:29 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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KB wrote on Fri, 16 January 2015 17:09
right after pulling back onto the freeway after the shattered window episode today,
we suddenly suffered a loss of power in 3rd gear. It was like it was somehow shifting from 2nd to neutral instead of 3rd.
Since we were already pretty shaken up by the broken window, this was really not helpful.
We pulled over to check the tranny fluid level, which was fine, and then limped home the remaining 30 miles or so in 2nd gear.

So, any thoughts on what to check? I'm thinking vacuum modulator line, or maybe the shift linkage.
Other ideas?

thanks,
Karen
1975 26'


Are you sure it wasn't shifting from 3rd to 2nd? Dan Gregg had that problem with his nearly new Manny tranny a few years ago and it turned out to be the governor. He replaced it and the problem was solved.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] 3rd gear loss of power [message #269824 is a reply to message #269821] Fri, 16 January 2015 20:41 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
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I hope it's something simple.

Larry Davick

> On Jan 16, 2015, at 6:22 PM, KB wrote:
>
> ljdavick wrote on Fri, 16 January 2015 16:44
>> Can you think of any reason why this might be related to the shattered window? Could there have been some debris on the road that hit the vacuum
>> lines, or something?
>
>
> it's possible; I'll get under there in daylight and see if there's anything obviously amiss.
>
> thanks
> Karen
> 1975 26'
>
>
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: 3rd gear loss of power [message #269829 is a reply to message #269803] Fri, 16 January 2015 22:47 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Look closely at both sides of the dipstick. If nothing found, then drain it and catch the fluid. Then pull the pan and see what, if anything is in the bottom of it.



Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: 3rd gear loss of power [message #269832 is a reply to message #269829] Fri, 16 January 2015 23:32 Go to previous messageGo to next message
hal kading is currently offline  hal kading   United States
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Karen,

While not exactly the same symptoms as yours, we had the nylon governor gear shear, but it wasn't a clean break. there was enough friction that the transmission would act normal part of the time and flaky part of the time. Not too bad a job to pull the governor and check.

Hal Kading 78 Buskirk Las Cruces NM
Re: 3rd gear loss of power [message #269846 is a reply to message #269797] Sat, 17 January 2015 08:27 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Karen, you said Ragusa pan. That coupled with the "chinese filter syndrome" with the mal fitting neck to valve body sizing could allow the tube to drop down enough to suck air. When you drop the pan be observant of the filter being homed properly and that the O ring situation is ok. I don't guess you "smoked" the clutches by driving with it slipping or driving abusively at high trans temps. I would think shift quality would give you mire warning of tgat failure mode. Good luck.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: 3rd gear loss of power [message #269858 is a reply to message #269846] Sat, 17 January 2015 11:44 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I blew mine on the way to the Berrien Springs Rally. I stopped for a stop sign about 1/4 mile before the entrance to the rally and when I pulled away there was no 3rd gear. I slowed down and turned in to the rally and everything was fine. Of course at that speed I never got into 3rd gear. First and second worked normally. It was not until after the rally that I got up to 3rd gear again that absolutely nothing worked. I drove home in second. When checked the dip stick at the time and later pulled the pan there was finely ground up clutch stuff in the bottom and on the stick. There was no warning. It went from running fine at 55 to 60 mph to nothing.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: 3rd gear loss of power [message #269860 is a reply to message #269832] Sat, 17 January 2015 12:41 Go to previous messageGo to next message
KB is currently offline  KB   United States
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hal kading wrote on Fri, 16 January 2015 21:32
Karen,

While not exactly the same symptoms as yours, we had the nylon governor gear shear, but it wasn't a clean break. there was enough friction that the transmission would act normal part of the time and flaky part of the time. Not too bad a job to pull the governor and check.

Hal Kading 78 Buskirk Las Cruces NM


Hal, did you notice any weirdness with the speedometer while it was doing that? I thought maybe governor,
but the speedo was working fine.

thanks,
Karen
1975 26'
Re: 3rd gear loss of power [message #269862 is a reply to message #269822] Sat, 17 January 2015 12:57 Go to previous messageGo to previous message
KB is currently offline  KB   United States
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Quote:


Are you sure it wasn't shifting from 3rd to 2nd? Dan Gregg had that problem with his nearly new Manny tranny a few years ago and it turned out to be the governor. He replaced it and the problem was solved.


mostly sure... but you know how these things are when you're under stress.
The symptom was it would "whir" (higher RPM) as if it was suddenly in neutral with no load on the engine, and the speed would drop.
As we'd slow down it would go into 2nd. Then a little further on it would seem to be OK for a bit like 3rd was working, then not. It became frequent (and scary) enough that we just dropped speed and went home in 2nd. We didn't seem to have any trouble in 2nd or 1st, except when I restarted it in the driveway after it had been sitting a couple of hours and it would go into some gears, but then wouldn't, but then would.

thanks,
Karen
1975 26'


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