Renevette1982

Dear members, today i noticed that the 700R4 auto trannie of mij '82 Crossfire Injected started to slip.

In normal D position i can hear the trannie slipping to 3500 to 4000 rpm wih almost no power transfer. In position 3 almost the same, only in position 2 the car is drivable. When i got out of the car i noticed a slight "burned clutchplate" smell. I have smelled this before but without any slipping. Today the unit suddenly started to slip.

I know the transmission is leaking a bit, can this be just an oil shortage or do i have to consider a rebuild?

Motorvation

Oil level must be perfect. First steps here…

Steve O.

Buccaneer

Check the tranny fluid, you are probably low and that will burn it up if low enough and driven.

Eric P

Make sure the TV cable is hooked up to the throttle

4-vettes

I don't know much about automatics. In fact you could fill volumes with what I don't know.
But this much I do know, if a auto trans starts to slip. The FIRST thing to check is the fluid level. Driven low on fluid. And you do need a rebuild!

Renevette1982

Damn, just checked oil level and it seems good, above the upper mark at a cold engine.

Could it do any harm if i add a bit of ATF anyway?

Or can i start saving for a trannie rebuild?

johnt365

If I was in your shoes and was facing a transmission rebuild or replacement, and the current transmission was still in stock form, I would install a shift recalibration kit first and see what happens.

Even the techs at Trans Go will tell you putting a "Shift kit" in an old transmission could cause it to go out faster. But, if you are prepared to rebuild it anyway, does that matter? What if it just needs a little more pressure to work properly?

I had bought a used 2004R that was slipping on the 2-3 shift for $145. Installed a kit including a larger boost valve and billet servo and haven't had any issues since.

I installed a Trans Go kit in a 4L60E in a 95 van that was acting up, with a larger boost valve, and haven't had any issues since.

Sonnax and Trans Go both make kits for the 700R4. If increasing the pressure and the kit doesn't fix the problem, you were already going to rebuild it. Plus, you can use the kit in the rebuild if the trans was too far gone.

Here's what I would try:

https://transgo.com/product-details/...-boost-valves/
https://transgo.com/product-details/700-shift-kit/

Tim7282

Check the trans fluid with the car warmed up and running on a level surface. It says that right on the dip stick. A cold, non running check will show it perfectly full when it is not.

Renevette1982

Man i hope you are right.

Wasn't able to get any ATF today as all shops are closed so i could not add some oil.

But the car was always in good shape but wasn't driven for two months. Now i drove it and noticed clutch slipping immediately. A gearbox wouldn't just instantly start slipping from standing still right?

Only thing changed was quite a puddle of trannie oil on the street where it was parked.

I'll top it off and keep my fingers crossed.

gjohnson

If your smelling it, prob. toast. Time for a rebuild

1860army

What Color is the fluid on the stick and how does it smell? If it's dark and smells burnt you have trouble, plus you have a sizeable leak to deal with. I used an old school trans guy to update my 700r4 and he told me that the first time they slip is the first time you should start thinking about a rebuild because they will always do it again... Good luck

60

Buccaneer

IMO, if the fluid level is checked correctly and is full, the TV cable is correct and it is leaking fluid, you have issues and you probably need a rebuild. The leak can be anything and it not affecting the slip issue, but there is something going on inside that isn't right whatever that is. Adding more than the full line on the stick is NOT a good idea. Installing a shift kit...again IMO is NOT the way to go here, even if it was to help. If it did help, that suggests you need a rebuild, there's an issue going on inside and clutches are probably bad along with other things. Just rebuild the trans by a very reputable shop. GL on whatever you decide to do.

Renevette1982

First best newyear wishes to everybody!

I will fill it up a bit and make sure it has a proper level reading, flat and on operational temperature.

If the box still slips i start saving for a rebuild, and if it doesn't i will do the same as it has shown a slight smell of burned clutches before. Maybe it is just the Old Lady's time after 42 years.

My '82 is completely stock and bij no means a powerhouse so just giving the tranny a good standard rebuild without any upgrades will be enough i hope.

I will keep you guys informed, thanks for the advise!

Buccaneer

There is a guy in the Netherlands that may be able to help you out on the trans rebuild. He goes by the screen name Twin Turbo. His first name is Marc. I do not remember the forum name anymore, but if you google maybe his screen name or Netherlands corvette forums, he may pop up. If you do find him or I find the site, tell him that Buccaneer/Tom from Arizona said hi. He used to be on the old Crossfire Injection forum back in the day. GL.