shudder and shake
Thread Starter
Team Owner
Joined: Feb 2005
Posts: 20,111
Likes: 1
From: My redneck of the woods louisiana
shudder and shake
when going down the road in OD in the 20-30 mph range my car feels like it's being jackhammered on it is a really violent shuddering 
and forces me to shift it down to D whch stops it, consiquently i ride around in D until over 40 mph
also at certain speeds and if i lightly accelerate it shakes everything up.
is this a tranny prob or TCC prob?
i'm tired of the screws falling out and watching my gauge cluster bounce up and down
help me please
TIA
and forces me to shift it down to D whch stops it, consiquently i ride around in D until over 40 mph also at certain speeds and if i lightly accelerate it shakes everything up.
is this a tranny prob or TCC prob?
i'm tired of the screws falling out and watching my gauge cluster bounce up and down
help me please
TIA
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
The engine has 5 main bearings. The rear bearing has lips that overhang the main bearing saddles. The 'lips" on the bearing ride against a flange on the crank. They work together to hold the crank in place(foward and rearward) If a clutch or torque converter put high force on the rear of the crank, it burns up the thrust bearing and "knocks out" the thrust. .005-.015 is typical thrust with .008 being about average.
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
...I know exactly what you mean now...didn't know they were called thrust bearings. What we ( in Australia) know as thrust bearings are the ones that operate off a clutch throw out arm/fork in manual transmissions. But thanx for clarifying that...
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
Pete.....Speaking of shuddering...in my 87 A4 I had a trans oil leak after rebuilding my car. This included having a trans seal kit fitted and rebuilt tc. It started leaking within 300 miles. Turns out that the fr. bearing was pushing on the lip of the seal....Remove trans. , fit new bearing, Loctite bearing in, new seal, trans. back in. I then used the car in an autocross style event, and the front seal blew out again...!
I had the trans. rebuilt again, this time with a new fr. bearing, cross hatched mating surfaces, Loctited, and peaned in place....
The question now is...do I need to balance the drive-shaft, even though there is no vibration evident while driving, or was the last fitment sufficient to prevent the seal blowing out again..?
Any input on this appreciated.
I had the trans. rebuilt again, this time with a new fr. bearing, cross hatched mating surfaces, Loctited, and peaned in place....
The question now is...do I need to balance the drive-shaft, even though there is no vibration evident while driving, or was the last fitment sufficient to prevent the seal blowing out again..?
Any input on this appreciated.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
GM used a small tin ring that tapped over the front seal as a band aid fix for this type of problem. What you are describing was a common problem on the 85 and prior pumps. GM drilled the drain hole in the pump housing larger to aleviate some of this. The larger holes and pump seal retainer were(combined) a good fix. Rather odd to have happen on your unit. Maybe an 84 unmodified trans was swapped in earlier in it's life? Hopefully you have the problem licked. I would certainly try rotating the driveshaft 180 degrees. The shaft and yoke had paint marks on eack to indicate the heavy side. Most guys see this and line them up, when in fact, they should install them opposite of each other.
Last edited by Pete K; Feb 17, 2006 at 09:19 PM.
Racer
Joined: Nov 2004
Posts: 445
Likes: 0
Gotta hand it to you, Pete..you know your stuff. My car is a "bitsa"...86 body, 87 motor and 85 trans., with a later model pump(11 or 13 vane, can't remember).
I fitted the drive-shaft without the yoke being removed before-hand..
Thanx for the tips on the oil pump housing..
I fitted the drive-shaft without the yoke being removed before-hand..
Thanx for the tips on the oil pump housing..
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Originally Posted by CorvAdel
Gotta hand it to you, Pete..you know your stuff. My car is a "bitsa"...86 body, 87 motor and 85 trans., with a later model pump(11 or 13 vane, can't remember).
I fitted the drive-shaft without the yoke being removed before-hand..
Thanx for the tips on the oil pump housing..
I fitted the drive-shaft without the yoke being removed before-hand..
Thanx for the tips on the oil pump housing..
Thread Starter
Team Owner
Joined: Feb 2005
Posts: 20,111
Likes: 1
From: My redneck of the woods louisiana
i was hoping it wasn't something too expensive
would a reputable tranny guy be able to determine what the problem is before i shell out the big $$?
can i tell what year my tranny is? (although i'm pretty sure nobody has ever laid a wrench on this car)
will this from madvet help because it seems that the tcc is locking up when i don't want it to
would a reputable tranny guy be able to determine what the problem is before i shell out the big $$?
can i tell what year my tranny is? (although i'm pretty sure nobody has ever laid a wrench on this car)
will this from madvet help because it seems that the tcc is locking up when i don't want it to
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Originally Posted by wht_slvr_86
i was hoping it wasn't something too expensive
would a reputable tranny guy be able to determine what the problem is before i shell out the big $$?
can i tell what year my tranny is? (although i'm pretty sure nobody has ever laid a wrench on this car)
will this from madvet help because it seems that the tcc is locking up when i don't want it to
would a reputable tranny guy be able to determine what the problem is before i shell out the big $$?
can i tell what year my tranny is? (although i'm pretty sure nobody has ever laid a wrench on this car)
will this from madvet help because it seems that the tcc is locking up when i don't want it to
I have used that kit from MAD and it works well. I stopped using it because I typically install a 1 wire lock up, 4th gear only kit in most I do. They simply and inexpensively cause the trans to lock the converter in 4th gear only. I too like the drivability this way. No bucking or rumbling from the converter being locked up too early.
On the pass side of the case, just above the pan gasket, in the rear there is a flat pad with numbers stamped in it. Grab a brill or scrubbly pad and some carb cleaner. get the code and post it. I will decode it for you.
