Feb 23, 2015, 02:26 PM
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Loud clunk when i put it in drive???
Thread Starter
Instructor
Joined: Sep 2008
Posts: 100
Likes: 0
From: Oak Forest IL
Loud clunk when i put it in drive???
I have a 1990 c4 automatic when i put it in gear in makes a pretty heavy clunk...Maybe U joints, but i went under the car and checked and everything was tight so i have no idea
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
mine does/did this too.
my tranny leaks a bit, and when i fill it up with fluid it is less noticable..but still there.
I don't know what its from. i've learned to ignore it. once it blows up, i'll replace it.
my tranny leaks a bit, and when i fill it up with fluid it is less noticable..but still there.
I don't know what its from. i've learned to ignore it. once it blows up, i'll replace it.
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
if you wait till the idle goes back down to 600 rpm after the computer goes through it's self check, it will be less noticeable.
If you stick it in drive or reverse when it's about 900-1000 rpm, remember, at 900 RPM, that's 45 mph, with TPI, that's a lot of torque.
I think they fixed that problem in 1988 with a valve body bleed-off orifice.
If you stick it in drive or reverse when it's about 900-1000 rpm, remember, at 900 RPM, that's 45 mph, with TPI, that's a lot of torque.
I think they fixed that problem in 1988 with a valve body bleed-off orifice.
Melting Slicks
Joined: Mar 2008
Posts: 2,453
Likes: 347
From: SC
Pro
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
If
the vehicle has high miles (over 100K) the Ujoints are probably worn. I'd replace them as preventive maintenance before they fall out on the highway
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Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
because we have already been through the panic factor, and we know what to expect.
at 100K, I changed u joints (all 6) bead blasted the parking brake shoe backing plate, resanding the parking brakes, sanded the rear brake pads, had the rear discs turned, changed front brakes, new front rotors, new master cylinder, new brake booster, bled the brake system, changed the tie rods, steering rack, had it aligned, replaced the plastic window tracks, had the seats and steering wheel redyed, new wipers, new heads, new radiator, new radiator and heater hoses, new mufflers, installed polyeurethane shock absorber biscuits, new air conditioning compressor, new fuel hoses, replaced the injectors, fuel filter, I figure I could get another 100,000 miles out of it if I did it right.
It's still going strong, it has 144,000 now.
at 100K, I changed u joints (all 6) bead blasted the parking brake shoe backing plate, resanding the parking brakes, sanded the rear brake pads, had the rear discs turned, changed front brakes, new front rotors, new master cylinder, new brake booster, bled the brake system, changed the tie rods, steering rack, had it aligned, replaced the plastic window tracks, had the seats and steering wheel redyed, new wipers, new heads, new radiator, new radiator and heater hoses, new mufflers, installed polyeurethane shock absorber biscuits, new air conditioning compressor, new fuel hoses, replaced the injectors, fuel filter, I figure I could get another 100,000 miles out of it if I did it right.
It's still going strong, it has 144,000 now.
Last edited by coupeguy2001; May 28, 2009 at 12:03 AM.
Pro
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
Safety Car
Joined: Jul 2003
Posts: 4,928
Likes: 1
Pro
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
It's
a possibility, really need a tranny shop to check that out, one other possibility is worn ring and pinion gears...
Advanced
Joined: Jul 2008
Posts: 76
Likes: 0
From: SANDY UT
josephf31 had the right idea. gears loose or the output shaft on the trany may be worn, it takes a lot to break it but the teeth can wear and get loose on the yolk to the drive shaft or also check from the drive shaft to the rear end. if you do the drive shaft u-joints, do one at a time and take the rear off first and then try to spin it when still hooked to trany and feel for play then do the same to the rear. just have one side still hooked up each time so you dont fight the rear and the trany at the same time.
Racer
Joined: Sep 2008
Posts: 273
Likes: 0
From: Tallahassee Florida
I've had mine checked at AAA Transmission and they said there wasn't anything wrong.. My 84 has 79,xxx miles now and its done it since I rolled 65,000... Trans and car runs fine I learned to ignore it