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Tranny acting up

E

Eagle85C4

Guest
Hello all...
Well the tranny in the 85 is acting strange...when cold it does not want to shift, as it warms up it will shift but it takes a while, it will shift into second at about 35 mph. When warm it will shift into second around 22, third at 45, forth at 55. The tranny was flushed last June prior to driving it home from Virginia to Ohio. Until now it was flawless....
Second, something is wrong with the rear or drivetrain. Once underway, if you let off the gas it is like the rear of the car does a little fishtailing, now that is not turning the tires over, it feels like the left tire starts to pull, then switches to the right then back again. You can really feel it in the seat of your pants. If you turn the wheel back and forth it appears the car is solid, it just happens when you give it gas or let off. Could rear bearings or u-joints cause something like this? Thanks ahead of time...
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Hmmmmm

One...
How is the fluid color?
( repost)
How many miles on the tranny and how clean is the fluid? you might want to do a service on it first, drop the pan..change the filter observe the junk in the tranny pan etc.

The TV( throttle valve ) cable which contols the internal pressures of the tranny controls how HARD the shift is.. which MIGHT control your perception of the shift points. The tighter the cable, the harder the shifts.

WARNING,,If the TV cable is adjusted to loose your internal pressures will be off allowing clutch slipage so proceed with this knowledge.

Mark where the cable is currently ( scribe the plastic shell with a SHARP awl) .Next to the base of the TV cable bracket is the adjuster
mechanism with a half moon piece of metal facing out..press that in and push the cable nose in a couple of clicks. Did it change things?

As far as the rear end

Get the car in the air.... grab the rear wheels @ 12 & 6 O'clock

and rock
Top away from you
bottom towards you
then reverse.

This will tell you your bearing runout if you have more that 1/4 inch.. that's bad.

If your unsure try the fronts.. hopefully their tighter.. to give you the correct "feel".

Check closely the 1/2 shaft u joints.

Mine looked ok visually but applying the E brake and putting the car in rev & drive showed some BIG play in the U joints.

I'll bet your right side rear is worse then the left.

Mike

Mike
 
E

Eagle85C4

Guest
Well Mikey....
I got home early and jacked up the passenger side rear. To my surprise I found the shock ready to fall off the bottom, nut was three threads away from going bye-bye. Checked for movement top to bottom....not too bad but if you grab at 8 and 2 there is a bunch of movement. Then I rotated the tire and heard a bunch of noise from underneath, and again you are correct, both u-joints are BAD on the half shaft I have read the book, and it says to completely tear down that side. looking up under there it looks like I can remove caps from both ends and remove the shaft to replace the u-joints, versus removing spindle and all. I will replace the bearings in May when the lottery check arrives as well as the tires, rims, rotors, brakes, and all the rest of the u-joints. So sunday it is supposed to be 50 degrees out, crazy for Feburary here, and do the u-joints on the half shaft.

Thanks for the reply Mike, BTW you never told me what the transistors were in the cluster...did you find a generic replacement? Inquiring minds want to know. Thanks again my friend...

Oh fluid is fine..looks good smells good, have not tasted it yet...
Wish I had known about the flushing, would not have done it.
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Transistor

Never found a sub.. but I had SO MANY dead dashes from cracked glass/fire etc that I have about 10 good ones. Not pressing at this time to find a sub.

EEeeeeeKKK
YOU FLUSHED!
I would change the filter as soon as possible
I'll bet even money that the filter is clogged.
I would also tighten up the TV shift cable
(allowing more pressure into the clutch packs)

Easy-cheap-easy-cheap...Hmmmmm

Ok you CAN get the 1/2 shafts out without taking out the bearing but it's a bit of a job.

You do have to remove the X link bar & undo the spring & shock to be able to flex the trailing arm JUST enough to clear the diff yoke.

I did it..it wasn't fun and you 'll have to do it again when you replace the bearing.

Mike
 
E

Eagle85C4

Guest
Do you have a damaged cluster you might like to part with? I would love to have a crack at the guts of one. I am sure we could come to some agreement.

Called for ujoints at napa... 7.99 for drive shaft, 18.99 for the half shafts. I trust the parts from them. Dana Corp. owns Napa Spicer Gears and Mr. Gasket. You can see the difference in the ujoints from them then Pep Boys.

Thanks for the shaft info....it will be nice to get the wrenches in the hands from the winter layoff....
Take care...
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
One small problem

I do not own the clusters.. they belong to George who owns......

Sport Imports
Corvette/Viper/Miata

Parts & More

1-818-765-3333

( So much for the shameless plug )


What part of the cluster are you interested in?

Mike
 
E

Eagle85C4

Guest
I am an engineer for a phone company...I just want to take one apart and see what it is about. Chances are I will be able to find a replacement transistor for the one that goes bad. I have several delco radios and parts around for which I have schematics, it may be possible to cross the transistor from one of those. Just curious you know....
Take care...
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Oh believe me

I know.. let me ask george if i could send you an 84 broken dash ( but complete )

He's got a TON of those.


Mike
 
E

Eagle85C4

Guest
Great...well getting ready to go outside and change tranny filter and do the half shaft....wish me luck.

Tightned the shock and rear still moves around when giving it gas and letting off. I think I may need to redo all the bushings in the rear. Car has 140,000 miles on it, probably time....
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Good Luck

God's speed
no broken knuckels

Mike
 
E

Eagle85C4

Guest
Well, I found out what was causing the movement in the rear....passenger side half shaft had both u-joints ready to fall out. Both ujoints were missing all the needle bearings. This in turn caused the tire and related assembly to move in other then a straight line. To replace them I did not have to disassemble and remove the rotor, caliper and bearing. Using Mike's advice I removed the shock from the bottom, loosened the spring, and removed the bolt and dropped the crossbar.pulled the shaft up at the rear, watched the caps fall off the ujoint the slid it out of the yoke on the spindle and out it came. Replaced the bad joints and put it all back together. 2.5 hours...
Tomorrow I plan to change the tranny filter, as it now shifts ok, but I trust Mike's advise and I believe in preventitive maintenance. Thanks for all the help!!!
 
E

Eagle85C4

Guest
Well I changed the filter.It helped some but it still does not act right when cold. Is there any additive available to clean out tranny? I feel like something is sticking and need to be loosened up.
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
When it's cold

Will it not go into O/D?

How much junk did you get out of the pan?


Mike
 
E

Eagle85C4

Guest
Well Sir Mike....

It will go into overdrive once good and warm, not until. Now something else I noticed, it does not seem to go into lockup. Now on my Blazer you can definately tell when it goes to lockup, plus just a tap of the brake pedal will cause it to drop out of lockup....the vette does not go into lockup. Now it is my understanding that you can get the trannies with or without lockup. Is there a way to tell?
The magnet in the pan had a bunch of gunk on it, but overall there was very little other then fluid in the pan. Gonna try the duralube tranny stuff or an equivelent. Only other choice is to get factory rebuild for a grand.
 
7

78SilvAnniv

Guest
tranny additives

I have been getting advice regarding my '78 TH350 and I've had two ASE transmission guys tell me to not use additives except for TransX which IS good for trannys.
Hope yours turns out all right in the end. We're planning on tearing into ours this uninterupted weekend.
No plans, but the trans....
Silver
 
E

Eagle85C4

Guest
Well I dumped in some additive it seems to be getting better...time will tell.

Still no answer on the lockup question... Hib or c4c5 got any answers?
 

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