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Is My Tranny Shot [message #371319] Mon, 08 May 2023 07:36 Go to next message
Bruce Hart is currently offline  Bruce Hart   United States
Messages: 1500
Registered: October 2011
Location: La Grange, Wyoming
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Senior Member
I had my coach over at a friends house four blocks away from my house as he has a separate cement pad large enough to raise the coach so as I could work on the underside and check out a few things.

Yesterday I was checking the total timing on 1977 Kingsly coach with a 403 engine. I set the idle at 2900rpm, set timing, and noticed fumes coming out of the tranny fill tube and also noticed small amount out of where the tube is inserted into the final drive. I looked around to see if maybe some oil had spilled on exhaust manifold but it was coming out of the tranny fill tube. Had fumes for about 10 seconds and they subsided.

Corrected timing. Started to rain a bit so I went home and waited for the storm to pass. Lowered coach off of jack stands and proceeded to take coach back to the house. Started right up shifted into reverse with a loud bang and moved backward. Shifted into Drive and proceeded home. As I was lining coach up to the side of the house I had to moved forward and back to get parallel to garage side. At one time the coach would not engage either in reverse or Drive and just sat in the middle of the street. Finally, tranny engage in reverse, and I was able to park it.

Looking at a camping trip this Mother's day weekend 60 miles away

I would imagine that I burned up a clutch or two in the tranny.


Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: Is My Tranny Shot [message #371324 is a reply to message #371319] Mon, 08 May 2023 12:09 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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Registered: January 2009
Location: Tucson, AZ.
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It sounds like you have a leak. It will act that way if the transmission is low on fluid. Check it and top it off. Hopefully you didn't do any damage.

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: Is My Tranny Shot [message #371325 is a reply to message #371319] Mon, 08 May 2023 12:59 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Could be low…. But probably not…

But that most likely sounds like tranny is done. Sorry..


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Is My Tranny Shot [message #371327 is a reply to message #371325] Mon, 08 May 2023 13:47 Go to previous messageGo to next message
Bruce Hart is currently offline  Bruce Hart   United States
Messages: 1500
Registered: October 2011
Location: La Grange, Wyoming
Karma: 5
Senior Member
Took coach out this morning and got up to 60mph with no issues. Got the tranny fluid hot and looks to be a quart low. This coach has been sitting idle for at least the past 4 years and possible the past 10 years. I did drive it 120 miles last July to my home where the tranny shifted hard but the records state that a shift kit was installed 20 years back. My thoughts are that it shifts hard do to a shift kit.

Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: Is My Tranny Shot [message #371329 is a reply to message #371319] Tue, 09 May 2023 15:00 Go to previous message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
1 quart is a lot to be low. If pump sucks air you get foam a false high reading. I’d add Dex/Merc till full running in park. Then test drive. If looking brown or burnt the Mity Vac fluid tool is great to remove old through dipstick. Then add fresh. Repeat.

John Lebetski
Woodstock, IL
77 Eleganza II
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