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transmission crud ? [message #360313] Fri, 27 November 2020 17:34 Go to next message
hertfordnc is currently offline  hertfordnc   United States
Messages: 1164
Registered: September 2009
Location: East NC
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Senior Member
The ATF has about 1000 miles on it since rebuild SEVEN years ago.

I dropped the pan to change the filter. There was fine sand-like deposits on the surfaces, big enough to feel between my fingers.

ATF is very dark.

photo here:

http://silvabullets.com/gmc_manifold/20201127_133358.jpg


Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.

[Updated on: Fri, 27 November 2020 17:46]

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Re: transmission crud ? [message #360314 is a reply to message #360313] Fri, 27 November 2020 18:17 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Registered: May 2011
Location: Braselton ga
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Senior Member
The symptoms indicate4 your transmission is slipping and getting hot. The 'sand' is friction material from the clutch(es). Ask Manny Travao what might be done to stop this, if anything can, before it fails and you hafta R & R and have it rebuilt.


--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 crud ? [message #360315 is a reply to message #360313] Fri, 27 November 2020 18:06 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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On Fri, Nov 27, 2020 at 3:47 PM dave silva via Gmclist <
gmclist@list.gmcnet.org> wrote:

> The ATF has about 1000 miles on it since rebuild SEVEN years ago.
>
> I dropped the pan to change the filter. There was fine sand-like
> deposits on the surfaces, big enough to feel between my fingers.
>
> ATF is very dark.
>
>
> --
> Dave & Ellen Silva
>
> 1972 Revcon Olds 455, toro drive train. All Stock
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.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 crud ? [message #360316 is a reply to message #360315] Fri, 27 November 2020 18:12 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
`Must not been a great rebuilt.
If material is soft, it should be the friction material.
If metallic, torque convertor or other.
One thousand miles and it is not fresh red color, than the clutch plates
were slipping and burning.
Take the trans back to the shop and request they do it right.

On Fri, Nov 27, 2020 at 4:06 PM Jim Kanomata wrote:

>
>
> On Fri, Nov 27, 2020 at 3:47 PM dave silva via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> The ATF has about 1000 miles on it since rebuild SEVEN years ago.
>>
>> I dropped the pan to change the filter. There was fine sand-like
>> deposits on the surfaces, big enough to feel between my fingers.
>>
>> ATF is very dark.
>>
>>
>> --
>> Dave & Ellen Silva
>>
>> 1972 Revcon Olds 455, toro drive train. All Stock
>>
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.gmcrvparts.com
> 1-800-752-7502
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
_______________________________________________
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Unsubscribe or Change List Options:
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] transmission crud ? [message #360317 is a reply to message #360316] Fri, 27 November 2020 18:49 Go to previous messageGo to next message
hertfordnc is currently offline  hertfordnc   United States
Messages: 1164
Registered: September 2009
Location: East NC
Karma: 0
Senior Member
jimk wrote on Fri, 27 November 2020 18:12
`Must not been a great rebuilt.
If material is soft, it should be the friction material.
If metallic, torque convertor or other.
One thousand miles and it is not fresh red color, than the clutch plates
were slipping and burning.
Take the trans back to the shop and request they do it right.



Returning it is not an option. I've been in touch with Manny about a replacement. I'm trying to understand what's going on and whether I can get a few miles from it in the local area.


Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
Re: [GMCnet] transmission crud ? [message #360320 is a reply to message #360317] Fri, 27 November 2020 20:21 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
Senior Member
hertfordnc wrote on Fri, 27 November 2020 18:49
jimk wrote on Fri, 27 November 2020 18:12
`Must not been a great rebuilt.
If material is soft, it should be the friction material.
If metallic, torque convertor or other.
One thousand miles and it is not fresh red color, than the clutch plates
were slipping and burning.
Take the trans back to the shop and request they do it right.



Returning it is not an option. I've been in touch with Manny about a replacement. I'm trying to understand what's going on and whether I can get a few miles from it in the local area.
JMHO but you could try doing several quick trans fluid changes...complete changes. I did this on my Toyota Prius with VERY DARK trans fluid, and 70K miles later, still driving it, still pink on yearly changes. Go out and buy the cheapest trans fluid you can get your hands on. Drain fluid, including the torque converter. Drop the pan, change the filter and refill with fresh trans fluid. Take the coach for a 10 mile or so EASY drive. Change the fluid again. Take for another 10mile drive. By now the fluid should be coming out pretty pink. If not, do another change. Do your final change to a brand name fluid either Dino or Synthetic. Now drive it and see what happens. During the first change, take a sample and send to Blackstone labs. They can tell you what is going on inside and help you decide what to do next.
https://www.blackstone-labs.com/?session-id=lh1ef2550diahc45zo1cyrul&timeout=20&bslauth&urlbase=https%3A%2F%2Fwww.blackstone-labs.net%2FBs tone%2F%28S%28lh1ef2550diahc45zo1cyrul%29%29%2F

Doing this may or may not help your problem, but is cheaper than a rebuild and if it does not solve the issue, you've only lost time and several gallons of cheap fluid.
This is how I do a complete fluid change. This is a very messy procedure; you're gonna spill fluid, so be prepared with dry rags and the like to clean-up afterwards.

1. Do this with the trans cold. Wait at least over night.
2. Raise the coach high enough to get a 5 gal pail under it with room to
spare.
3. Disconnect both trans lines at the radiator, and be prepared to catch the
fluid coming out of the cooler in the radiator.
4. Attach hose extensions to the lines and drop the lines into the 5 gal
pail.
5. Using two people, start the motor for only couple of seconds. Do this to
identify which line the fluid will come out of. Now you know which line you
*must* keep in the bucket.
6. Again, using two people, (one to run the motor, the other to watch the
fluid) start the motor.
7. Run the motor until the fluid line begins spurting air. Shut motor off
immediately! The fluid will get quite frothy.
8. Allow to stand without the motor running for 4-5 minutes. This will let
excess fluid in the trans drain down into the pan.
9. Start the motor again for no more than 5 seconds. Shut off the motor.
This will pump out that last little bit in the pan and make dropping the pan
a lot less messy.
10. Let the oil lines drip into the pail while you drop the trans pan.
11. Drop the trans pan, and replace the filter using two (2) "O" rings at
the filter.
12. Hook up the two trans lines to the oil cooler at the radiator.
13. Fill the trans with about 7 quarts of trans fluid.
14. Start the motor and allow to idle for about 30 seconds or so before
checking fluid level.
15. Check fluid level and add accordingly.
16. Once full, drive until normal operating temp is reached, and recheck
fluid level. Add fluid to bring to "Full".

I've used this procedure on every auto trans that I've owned for .... well
.... forever.

This is just the way I do it....no guarantee it will fix your issue.

Just my relatively informed, off the cuff, back yard mechanic, gut level,
eyeball it up and guesstimate, way of doing things....that's all...


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: [GMCnet] transmission crud ? [message #360324 is a reply to message #360320] Sat, 28 November 2020 00:50 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
Am I hearing that the trans came from Manny?
If it did I know he will work with you.
Feel like you must had a reason to change fluid when you did.

On Fri, Nov 27, 2020 at 6:22 PM Larry via Gmclist
wrote:

> hertfordnc wrote on Fri, 27 November 2020 18:49
>> jimk wrote on Fri, 27 November 2020 18:12
>>> `Must not been a great rebuilt.
>>> If material is soft, it should be the friction material.
>>> If metallic, torque convertor or other.
>>> One thousand miles and it is not fresh red color, than the clutch
> plates
>>> were slipping and burning.
>>> Take the trans back to the shop and request they do it right.
>>
>> Returning it is not an option. I've been in touch with Manny about a
> replacement. I'm trying to understand what's going on and whether I can get
>> a few miles from it in the local area.
>
> JMHO but you could try doing several quick trans fluid changes...complete
> changes. I did this on my Toyota Prius with VERY DARK trans fluid, and 70K
> miles later, still driving it, still pink on yearly changes. Go out and
> buy the cheapest trans fluid you can get your hands on. Drain fluid,
> including
> the torque converter. Drop the pan, change the filter and refill with
> fresh trans fluid. Take the coach for a 10 mile or so EASY drive. Change the
> fluid again. Take for another 10mile drive. By now the fluid should be
> coming out pretty pink. If not, do another change. Do your final change to a
> brand name fluid either Dino or Synthetic. Now drive it and see what
> happens. During the first change, take a sample and send to Blackstone
> labs. They
> can tell you what is going on inside and help you decide what to do next.
>
> https://www.blackstone-labs.com/?session-id=lh1ef2550diahc45zo1cyrul&timeout=20&bslauth&urlbase=https%3A%2F%2Fwww.blackstone-labs.net%2FBs tone%2F%28S%28lh1ef2550diahc45zo1cyrul%29%29%2F
>
> Doing this may or may not help your problem, but is cheaper than a rebuild
> and if it does not solve the issue, you've only lost time and several
> gallons of cheap fluid.
> This is how I do a complete fluid change. This is a very messy procedure;
> you're gonna spill fluid, so be prepared with dry rags and the like to
> clean-up afterwards.
>
> 1. Do this with the trans cold. Wait at least over night.
> 2. Raise the coach high enough to get a 5 gal pail under it with room to
> spare.
> 3. Disconnect both trans lines at the radiator, and be prepared to catch
> the
> fluid coming out of the cooler in the radiator.
> 4. Attach hose extensions to the lines and drop the lines into the 5 gal
> pail.
> 5. Using two people, start the motor for only couple of seconds. Do this to
> identify which line the fluid will come out of. Now you know which line you
> *must* keep in the bucket.
> 6. Again, using two people, (one to run the motor, the other to watch the
> fluid) start the motor.
> 7. Run the motor until the fluid line begins spurting air. Shut motor off
> immediately! The fluid will get quite frothy.
> 8. Allow to stand without the motor running for 4-5 minutes. This will let
> excess fluid in the trans drain down into the pan.
> 9. Start the motor again for no more than 5 seconds. Shut off the motor.
> This will pump out that last little bit in the pan and make dropping the
> pan
> a lot less messy.
> 10. Let the oil lines drip into the pail while you drop the trans pan.
> 11. Drop the trans pan, and replace the filter using two (2) "O" rings at
> the filter.
> 12. Hook up the two trans lines to the oil cooler at the radiator.
> 13. Fill the trans with about 7 quarts of trans fluid.
> 14. Start the motor and allow to idle for about 30 seconds or so before
> checking fluid level.
> 15. Check fluid level and add accordingly.
> 16. Once full, drive until normal operating temp is reached, and recheck
> fluid level. Add fluid to bring to "Full".
>
> I've used this procedure on every auto trans that I've owned for .... well
> .... forever.
>
> This is just the way I do it....no guarantee it will fix your issue.
>
> Just my relatively informed, off the cuff, back yard mechanic, gut level,
> eyeball it up and guesstimate, way of doing things....that's all...
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org



Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] transmission crud ? [message #360326 is a reply to message #360324] Sat, 28 November 2020 06:45 Go to previous messageGo to next message
hertfordnc is currently offline  hertfordnc   United States
Messages: 1164
Registered: September 2009
Location: East NC
Karma: 0
Senior Member
jimk wrote on Sat, 28 November 2020 00:50
Am I hearing that the trans came from Manny?
If it did I know he will work with you.
Feel like you must had a reason to change fluid when you did.


It may have been a Manny Trans at one time but someone else worked on it and it is no longer on his books. But I'm not really trying to save it long term. If i can flush it and get it working right i'll drive the coach within tow range while I work on other stuff and put a new trans in over the next year or so.


Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
Re: transmission crud ? [message #360337 is a reply to message #360313] Sat, 28 November 2020 15:13 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
How’s it shifting? Feel like slipping or crisp shifts. You would have to feel it slipping to darken the fluid that much, unless there is some other explanation. Did the trans guy use the defective TH425 filter where it sucked air and whipped it into the fluid causing slip? 1000 miles is just 2 days of highway driving.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: transmission crud ? [message #360338 is a reply to message #360337] Sat, 28 November 2020 15:26 Go to previous message
hertfordnc is currently offline  hertfordnc   United States
Messages: 1164
Registered: September 2009
Location: East NC
Karma: 0
Senior Member
JohnL455 wrote on Sat, 28 November 2020 15:13
How’s it shifting? Feel like slipping or crisp shifts. You would have to feel it slipping to darken the fluid that much, unless there is some other explanation. Did the trans guy use the defective TH425 filter where it sucked air and whipped it into the fluid causing slip? 1000 miles is just 2 days of highway driving.


Given i only have about 18 miles driving ANY GMC it's hard to know how it's shifting but i would say it's mushy. Shifts are barely perceptible.

Nothing is known about the previous work done on the trans.



Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
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