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Transmission ?? [message #327384] Thu, 21 December 2017 10:42 Go to next message
Bierman is currently offline  Bierman   United States
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This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this normal? Is there an easy fix? Should I be worried
Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I am actually going 62

Thanks for any and all input


Member, GMCI, Sunshine Statesman and Dixielanders 26' 1978 Eleganza II, new(rebuilt by Sirum) 403, Lenzi hubs and knuckles, front end by Ferrara
Re: Transmission ?? [message #327385 is a reply to message #327384] Thu, 21 December 2017 11:32 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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You may be leaking fluid around the trans dipstick if it isn't well sealed. Or from any of a number of other places. Best chance is wipe it clean, run around a bit, and see what's damp.

--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: Transmission ?? [message #327387 is a reply to message #327384] Thu, 21 December 2017 12:59 Go to previous messageGo to next message
Tom Lins is currently offline  Tom Lins   United States
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Bierman wrote on Thu, 21 December 2017 11:42
This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this normal? Is there an easy fix? Should I be worried
Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I am actually going 62

Thanks for any and all input



If you have a tach you can use this table to figure out which final drive you have.
http://www.appliedgmc.com/level.itml/icOid/482



Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/
Re: Transmission ?? [message #327388 is a reply to message #327385] Thu, 21 December 2017 13:00 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Easiest way to check FD ratio would be driving a set speed, using the GPS, and check engine rpm with a tach. RPMs will give you an accurate idea of your final drive ratio. Record and report engine rpm at GPS speeds of 60, 65, and 70 mph. Smarter guys than me will give you an idea of your final drive ratio.
Tom


2012 Phoenix Cruiser model 2552 KA4CSG
Re: Transmission ?? [message #327389 is a reply to message #327384] Thu, 21 December 2017 14:37 Go to previous messageGo to next message
dshafer is currently offline  dshafer   United States
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Don't forget to consider tire size in your quest. Could also be that your chain drive has aftermarket gears. If your drive ratio is 3.21 the cover will only have eight bolts. All others have 10.


1977 26 foot 403
Re: Transmission ?? [message #327391 is a reply to message #327384] Thu, 21 December 2017 15:18 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Bierman wrote on Thu, 21 December 2017 11:42
This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this normal? Is there an easy fix? Should I be worried
Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I am actually going 62

Thanks for any and all input

Kevin,

Small leaks are not at all uncommon.

But:
3.55/3.07 = 1.156*55 = 63.6
An indicated 55 could easily be that far off.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Transmission ?? [message #327394 is a reply to message #327384] Thu, 21 December 2017 16:49 Go to previous messageGo to next message
NextGenGMC is currently offline  NextGenGMC   United States
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Can the speedometer error be due to the wrong plastic gear installed in speedometer output housing on transmission?
I suppose one can pull it out, count the number of teeth, and compare it to the RPM vs. speed ratio to make sure it is correct one for the final drive combination.


Bierman wrote on Thu, 21 December 2017 08:42
This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this normal? Is there an easy fix? Should I be worried
Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I am actually going 62

Thanks for any and all input



Vadim Jitkov '76 Glenbrook 26' Pullman, WA
Re: Transmission ?? [message #327397 is a reply to message #327384] Thu, 21 December 2017 19:11 Go to previous messageGo to next message
Bierman is currently offline  Bierman   United States
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Took the coach for a little ride today then went underneath, could not see any leaks, the area around the dips stick was dry before and after the ride.
My concern with the leak is its not there for a few weeks maybe 3 after a road trip then all of a sudden I have a 6/7 inch circle on my driveway, this is not the first time.
I do not have a tach to check rpm, I have come accustomed to knowing my actually speed with the 7 MPH difference.



Member, GMCI, Sunshine Statesman and Dixielanders 26' 1978 Eleganza II, new(rebuilt by Sirum) 403, Lenzi hubs and knuckles, front end by Ferrara
Re: [GMCnet] Transmission ?? [message #327399 is a reply to message #327394] Thu, 21 December 2017 19:37 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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You should contact us as we are the major supplier of final drives and can
assist you better. You do not need to purchase anything from us.

On Thu, Dec 21, 2017 at 2:49 PM, Vadim Jitkov
wrote:

> Can the speedometer error be due to the wrong plastic gear installed in
> speedometer output housing on transmission?
> I suppose one can pull it out, count the number of teeth, and compare it
> to the RPM vs. speed ratio to make sure it is correct one for the final
> drive
> combination.
>
>
> Bierman wrote on Thu, 21 December 2017 08:42
>> This is from a limited mechanical member. The transmission leaks out a
> little fluid after sitting for a few weeks abd after a road trip. Is this
>> normal? Is there an easy fix? Should I be worried
>> Also my speedometer reads 7 MPH slower than what I am going, I checked
> this out with gps and having another vehicle next to me, do not know what
>> the PO has put in for final drive. Is there something I can check to see
> what the final drive is? Fixes to this problem? So when I am driving 55 I
>> am actually going 62
>>
>> Thanks for any and all input
>
>
> --
> Vadim Jitkov
> '76 Glenbrook 26'
> Pullman, WA
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Transmission ?? [message #327404 is a reply to message #327384] Thu, 21 December 2017 20:38 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
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Things to check for the leak....
1. Dipstick O-Ring
2. Pan gasket
3. Pan gasket bolts (put a small o-ring around each.
4. Shift lever O-Ring
5. Downshift wire connection O-Ring
6. Vac modulator O-Ring



Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] Transmission ?? [message #327405 is a reply to message #327404] Thu, 21 December 2017 21:37 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Add to check transmission cooler lines where they attach to the top of the transmission. Use a flashlight. A leak there often runs down the front of the transmission and appears to be a pan gasket leak.

Emery Stora

> On Dec 21, 2017, at 7:38 PM, Ray Erspamer wrote:
>
> Things to check for the leak....
> 1. Dipstick O-Ring
> 2. Pan gasket
> 3. Pan gasket bolts (put a small o-ring around each.
> 4. Shift lever O-Ring
> 5. Downshift wire connection O-Ring
> 6. Vac modulator O-Ring
>
>
> --
> Ray Erspamer
> 78 GMC Royale
> 414-484-9431
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: Transmission ?? [message #327406 is a reply to message #327384] Thu, 21 December 2017 22:02 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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This is a definite maybe. Never heard of it happening to anyone but me. Just my luck.

http://www.gmcmhphotos.com/photos/g7115-transmission-leak.html

Just the other day finally saw the inside of a transmission case to see where this originated. Turns out it is a locator pin on the other side of this leak. Just what I found.


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Transmission ?? [message #327411 is a reply to message #327406] Fri, 22 December 2017 08:12 Go to previous messageGo to next message
Fipp is currently offline  Fipp   United States
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I too have speedometer issues but decided not to do much. My transmission leak mystified me also but found weep hole in the final drive leaking and the great Bob Dunohugh suggested leak in the seal between the transmission and final drive. Hello Bob, I think I finally got on this site, and tried to call you this morning. Merry Xmas everyone!

Scott D. Fippinger Aledo, Illinois 1976 Royale
Re: Transmission ?? [message #327419 is a reply to message #327384] Fri, 22 December 2017 10:53 Go to previous messageGo to next message
Bierman is currently offline  Bierman   United States
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Thanks for all the advice, it really helps to have so many chip in. After my Christmas get away I will be checking out all of the suggestions.

Enjoy the Holidays
Merry Christmas and God Bless


JIM K, When I call Applied should I ask for you?


Member, GMCI, Sunshine Statesman and Dixielanders 26' 1978 Eleganza II, new(rebuilt by Sirum) 403, Lenzi hubs and knuckles, front end by Ferrara
Re: Transmission ?? [message #327428 is a reply to message #327384] Fri, 22 December 2017 16:15 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Fluid leaks down from the torque convertor which raises the fluid level in the transmission pan over time. Could be you have a leak that is just higher than the normal fluid level. Once the torque convertor leaks down some, you get your leak.

Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Transmission ?? [message #327432 is a reply to message #327384] Sat, 23 December 2017 08:51 Go to previous messageGo to next message
Bierman is currently offline  Bierman   United States
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Could that be the reason why it takes a couple of weeks sitting in driveway for a leak to show? IS the torque convertor supposed to leak down?

Member, GMCI, Sunshine Statesman and Dixielanders 26' 1978 Eleganza II, new(rebuilt by Sirum) 403, Lenzi hubs and knuckles, front end by Ferrara
Re: Transmission ?? [message #327433 is a reply to message #327384] Sat, 23 December 2017 09:04 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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yes, and yes. What you need to do is after the coach sits long enough to show a spot, >then< wipe the transmission clean and see where it's oozing. Pan, dipstick, modulator and lines are the possibilities, with the first two being the most common. Since it's lower, the pan leaks, if any, will appear before the fluid rises enough to get to the dipstick tube or modulator opening. The problem is to get the pan dry and then inspect daily while the coach is level. Do this with an inspection mirror with a long holder, >do not< crawl under an unsupported coach. If you lose a suspension component while you're under an unblocked coach, you will probably die.

--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: Transmission ?? [message #327442 is a reply to message #327411] Sat, 23 December 2017 19:33 Go to previous message
Matt Colie is currently offline  Matt Colie   United States
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Fipp wrote on Fri, 22 December 2017 09:12
I too have speedometer issues but decided not to do much. My transmission leak mystified me also but found weep hole in the final drive leaking and the great Bob Dunohugh suggested leak in the seal between the transmission and final drive. Hello Bob, I think I finally got on this site, and tried to call you this morning. Merry Xmas everyone!

Fipp,

Welcome to the group/family/cult/asylum...

Glad you found your way here.

Before you and we go too far, please build a sigfile. The regulars here have them and it is not coincidence. You can do this at <Control Panel/Account Settings> and scroll down. Please put in a real name. We use those here so that when other owners from here meet you (and you will meet) they may have some idea who you are. You should include an short about the coach because there are differences and some matter a whole lot. And lastly, but not leastly is a sort of location. The half of this group that gets this as e-mail will never see the "Aledo, Illinois" in the header. This matters because other that may choose to lend assistance need to know if you are in striking range, and there are environmental issues that can be more easily cleared.

If you need assistance with the coach, you have come to the right place. But that is just the beginning. I do not know how long you have had the coach, but you will soon discover that connecting to this group makes you a part of a community that is helping and supportive to a level that astonishes many. This just one of the reasons that owners are so friendly. When you read here, you will hear of levels of assistance that most think are outlandish, but we have come to love. This solid community so reminds me of that of the watermen that are my world that I have taken to welcoming new people here much any new owner or vessel is welcomed there. So,

May the Good Lord bless this coach and all those that set forth within her.

Welcome "Fipp"

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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