4+3 trans/clutch problems
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Joined: Mar 2004
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From: West Des Moines IA
4+3 trans/clutch problems
1986 C4 with not quite 40,000 miles. I am experiencing bad slippage in 2,3,4 gears whether overdrive is engaged or not. I do not smell clutch. Is it possible that the overdrive unit is slipping rather than the clutch?? Thanks in advance for your help.
Racer
Joined: Dec 2003
Posts: 277
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The OD unit has a sprag in it that would provide direct drive even if the OD was bad. Sounds like the clutch is bad.
Melting Slicks
Joined: Jan 2014
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From: Lunenburg MA
As far as I know, the OD uses a clutch pack in both OD and direct drive. I'd make sure it's full of clean fluid. If it's 40K and never been touched, that would be a bad thing.
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Joined: Mar 2004
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From: West Des Moines IA
Last time I drove it I had a difficult time getting the light to go on or off and getting to go in or come out of OD as well. Carfax says the mileage is accurate but I have no way to confirm. Thanks for your help!!
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Joined: Mar 2004
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From: West Des Moines IA
The question of a clutch pack or not is what I am really having to wonder. I spoke with a local trans. shop and might as well have been speaking Chinese. I have never serviced the OD, but I haven`t put many miles on the car. Thanks much for your input!!
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Racer
Joined: Dec 2003
Posts: 277
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If the car goes in reverse and the vehicle moves the OD clutch plates are OK, assuming your clutch is good and not slipping as you indicate.
Suggestion; put the car in 3rd or 4th gear, OD off, can you move the car or does the clutch slip badly.??
Burning Brakes
Joined: Apr 2016
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I am certain the previous owner changed it at least once before but no idea how many miles it had been since that change.
I could not believe how disgustingly dark brown and thick the fluid had become. Hard to believe that GM recommended 30k changes.
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Joined: Mar 2004
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From: West Des Moines IA
Hi Frank, It moves fine, just slips under semi hard acceleration in every gear but first. No problems with reverse. I am thinking that the problem with it going in and out is, like you mentioned, tarnished or corroded electrical connection somewhere. It had began to slip long before I had the problem with engagement. Thanks again for your help!!
3rd Gear
Joined: Oct 2020
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Really confuzzed.
I bought a 88 4+3 a month ago. Previous owner said it needed a clutch. So I ordered a clutch kit and put it in,( yes it needed it badly.) I have bleed the system as told by the shop manual. I still have to pump pedal several times to get it in 1st and 2nd, then a few more times to get it to roughly go into reverse. Let out on clutch about 2 inches and the car starts to move then the clutch slips and won't back up. But it will move forward. I haven't made it out of the shop yet. This is very frustrating probably as some of you know. What is wrong with this thing? I own a 79, a 85, and now this 88, never encountered this issue before. Please help. Thanks.
Pro
Joined: Sep 2024
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Hi Frank, It moves fine, just slips under semi hard acceleration in every gear but first. No problems with reverse. I am thinking that the problem with it going in and out is, like you mentioned, tarnished or corroded electrical connection somewhere. It had began to slip long before I had the problem with engagement. Thanks again for your help!!