pletzvet

My 85 C4 is showing a couple of transmission quirks. First, I'm a relatively new corvette owner, but quite mechanical. I've been told that this car with 190,000 km had a transmission overhaul within the last 50,000. It shifts fine, all gears are smooth etc. Once when accelerating up a bit aggressively, it blew some fluid out and hit the exhaust, lots of smoke but everything still works fine. There doesn't seem to be any leaking at the front or rear seal after I wiped it down. Some have said that it if the 700 tranny (on all GM's) is overfilled this can happen as there is an overflow near the top of the tranny. I've also been told that the 700 tranny doesn't have a large enough return hole near the front seal and this can be fixed by drilling it a bit larger. Any thought or comments or experiences?

The second problem is I get a good vibration when it is unlocking the torque converter esp when there is a little torque being applied. Some have suggested it might be as simple as the torque converter switch and best to change that before pulling the tranny out. Comments??

Thanks!

Mo_Bandy

It is possible that the fluid level is high, they are a bit quirky with the fluid level...

If you are getting a vibration and it was recentl rebuilt, maybe try popping the converter cover off , mark one of the bolts and try rotating the converter one bolt and see if the vibrations goes away, it will either get better or worse.. you have 3 tries it could be that maybe the balance is off just a touch...

I hope this helps,

MO

j3studio

I can't even begin to describe the issues I think my A4 might have...

pletzvet

Thanks for the suggestion of giving the TC a partial rotation, MO_Bandy. Sorry for the delay in acknowledging your comments, I realized after posting on the "General" forum that I was asking more of a tech question so I re-posted the same question there. If there are other comments/suggestions (and I'd love to hear them!) perhaps it would be a benefit to others as well if we put them all in the in Tech forum. Once again, thanks for the response.
Dan

Redeasysport

Try doing an advanced search in the archives for 700R4 you'd be amazed.

DarkBlue88

If it's blowing it out the vent hole under load, just change the filter, that fixed my 89 pickup.

pletzvet

The more I read (and thanks for the feedback) the more I think I will try a few low cost ideas first - a good flush, new filter, fill to low side of full check the resistances when the pan is off and see if that changes things. I'll let you know how it turns out. Right now my (new to me) C4 is wrapped up and sleeping like a baby surrounded by a couple of feet of snow. Cheers!