enventr

I have a 95 LT1 auto.It has about 70,000 miles.I got the car about 5 months ago.I always change oil every 2k miles and trans fluid every year.I would like to change the fluid on the trans but am a little afraid because I had bought some years ago a Maxima.As soon as I changed the fluid (next day)the trans was slipping.I also helped a friend change his Honda prelude fluid (with honda oil)and that started slipping.
This could be the first time the fluid will be changed in the Vette.The previous owner said he did not remember if he had it replaced.I just wanted an opinion.The fluid is not bright red as it should but still seems ok.but slightly darker-brownish red not totally brown
Thanks

rocco16

Change the fluid.
I've changed trans fluid on lots of GM autos and have never seen a problem.
I'm guessing that your previous bad experiences were the result of not filling the trans to the proper levels, i.e. not using the proper method of checking for "full". ???
Follow the procedure in the service manual and you can't make any mistakes. If you don't have the factory service manual, get one.

Larry
code5coupe

Pete K

If it were mine, I would change it. Do NOT use sealer, rtv or other goop on the gasket. The "goop" could block the servo dump hole and burn up the trans. A thin coat of vaseline on both sides of the gasket is all that is needed. Torque bolts to 100 inch pounds. 1 hr later retorque. If at all possible, retorque them a 3rd time after a week goes by.

wisynoil

I would flush the whole system rather than just dropping the pan. I would also suggest you use a full synthetic ATF.

c4cruiser

Find a reputable shop (not a Jiffy Lube or any of those drive-through places ) that has the proper equipment to do a complete flush of the fluid. They will have a machine that flushes the old fluid from the tranny and torque converter and replaces with fresh fluid. They will also change the filter as part of that service.

I would stay with just Dexron III; synthetic ATF is expensive and if you do not much more than typical street driving, synthetic may not offer any improvement for the money.

BTW, oil changes every 2K miles is a bit much. An oil change every 3000 miles or 90 days is more than enough for the LT1. The motor requires a full synthetic (Mobil-1 5W-30) and it will easily handle extended changes. I only change oil in my cars one per year although my annual mileage only runs around 3500-4500 miles per year in each car. Even when I had my 92 vert, I only changed oil once in the fall. The oil stays fairly clean even after 4K miles.

enventr

Thanks guys ,I will absolutely change the fluid.I respect your opinions.

96 lt-4

i would change the fluid.i install a tranny cooler on everything i own.it is cheap insurance.
what your friends may have experienced is increased friction slipping.trans fluid thins over time and the fresh fluid may be too much for the clutch discs to grab.if the fluid is changed on a regular basis you won't have this problem.
i have seen more than one high mileage vehicle insist on changing trans fluid for the first time and see slippage.
the shop i work at discourages fluid changing(on high mileage vehicles where it has never been done before)for this reason.the customer never remembers you telling them this may happen and they blame you.

Daddy J

Pete K, our forum transmission guru, suggests Dino ATF rather than synthetic. (see his 11-23-06 Post " Auto trans fluid info" in C4 Tech /Perf) Also he has posted a lot of other good stuff there regarding transmissions which is well worth reading.
Thanks, Pete! I know I for one, and I'm sure many others, always appreciate your input.

enventr

I changed the fluid 6 days ago and it seems to be OK.I did not use the flush system this time because I was nervous the clutches in trans could not take it and start to slip.Just a new filter and fluid.I even thought about siphoning 2 quarts once in awhile and replace with fresh fluid.The pan looked clean without any particles.Thanks to everyone for your input.The shop overfilled and I siphoned to correct level thanks to CF.(see my thread dated 1-23-07 "trans. fluid level")

AORoads

Glad for the follow up and that everything is working just fine!

onedef92

Glad to hear. You changed the tranny filter too, right?

enventr

Yes-a new filter.The "X" brace was a pain on my vert.If it is not installed correctly it will vibrate like crazy on the exhaust pipe.This happened to me.Eventually I will get the fluid flushed.For now I will siphon 2 quarts out every now and then and replace with new fluid.
Thanks again to all CF members

Smooth

PETE IS THE MAN! Lots of good tips and facts!

f451degrees

mine rattles and drives me nuts! It got worse after the transmission shop change the filter and fluid. replacing the xbrace and now much worse..

how do you adjust it so it doesn't rattle, I have woodstove door sealing rope under it now till I figure out how to fix it right.

see you on the road

enventr

f451degrees
I took it to a corvette specialist near my house.He loosened the bolts only on the passenger front and took a small crowbar to re-adjust the position.This is the area that rattles against the exhaust pipe.He said there was a slot to move the position slightly-It only moved about 1/8 inch lower . but it solved the rattle problem.He is aware of this problem.This adjustment took him 3 minutes.Good Luck-let me know if you have luck with this.I tried to explain this to the transmission shop but they did not listen to my suggestion.It is a very easy fix but you need a lift,crobar and impact wrench.You will also have the same problem if you change the gas filter which I also did.

enventr

I have always read Pete k articles and hold him in high regard.He should open up a trans. shop.He will get paid for something that he enjoys.Not many of us can say that.Thanks Pete K. for your tips

f451degrees

thanks on that, need to replace the fuel filter for fun anyway. May as well try that then.

see ya on the road

Fast Cop

I changed the trans fluid and filter on my 96 vert about 3 months ago and I believe this was the first time and have not had a single problem since the change. Go for it. Do a DIY and enjoy

enventr

fast cop how many miles on your car?did you just drop pan and change oil or did you use flush method and change all of the oil?

corvetteronw

I went to a freebie Gordon Killebrew session while at FunFest last year. He had an A4 L98 sitting next to the tent and showed everyone how to change the fluid. I did not take notes but here is what I recall:
He had the top line from the tranny unbolted (the one that runs into the radiator/cooler). He had a rubber hose connected from that line in to a bucket. Car was in Park. He started it up and the old fluid pumped into the bucket. When it started to sputter he shut the engine off and filled the tranny with Mobil 1 synthetic transmission fluid (I forget how much though). He fired it up again and shut it off when fresh new fluid began to flow into the bucket.
He said that you should then reconnect the line and top off the fluid. Then drive the car around for a bit and check the fluid once more to make sure the level is correct. He also said that he has never seen a tranny filter that actually need to be changed! He said you could change it if it made you feel better but in his opinion one never has to drop the pan if you do the fluid change his way. He said that this method will work on all auto transmissions.
I'm sure this will elicit some comments.