My friend also got a 1998 C5 vert, but he's got an auto. When we ran the car on the Nordschleife, we got a message that the tranny oil was to hot running in the first lap (allthough it's a 20 km lap...)
I've read that this is an issue on these cars, but is it also an issue on the manual cars as I have?

 

typically not a problem with the manuals as long as you are not making really high hp numbers.

 

The ZO6 has a MN12 Trans Temp sensor. Its in the Oil Fill Hole.

When was the last time that you changed the MN12 Trans ATF?

Is it LOW???

If you got an over temp indication, I would drain it and fill it. It takes 3.75 quarts of Synthetic ATF If you can get it, I recommend AMSOIL Torque Drive ATF.

Your friends A4 Transmission could also be LOW. You have to have the car in the air to check the fluid. When you check the fluid level DO NOT REMOVE the fill plug if the engine is OFF!! The engine MUST BE RUNNING to properly check it.

You remove the pan to drain the oil and change the filter. To fill it, you have to remove the FILL PLUG on the drivers side of the trans, put as much ATF in as you can until it overflows, start the engine and run it till normal operation temp and then REFILL the pan (while the engine is running) until it overflows. Cycle it through the gears and refill it again. Once you put the cap back on, DO NOT REMOVE it if the engine is OFF.

It will puke out about 2 quarts of fluid.

Any A4 Corvette will require an additional transmission cooler if you run it very hard for a long distance.

What was your engine coolant temps when you were on the track with the 1998 A4?? You can install a cooler 160 Thermostat and have the coolant fans reprogrammed to come on sooner and stay on longer. That will help keep the transmission cooler.

 

Thanks for the input. No, I haven't seen a temp message on mine, I was just cuorious if it was a problem here too.

As for my friends A4, the engine temp was just fine during the track driving. It was just the signal for hot trans oil that came on. On the Nordschleife which is very long, we couldn't get one whole lap before the signal came. He will check/change fluid this winter.

 

Do the automatics also have a trans fluid cooler in the radiator? All my c5's have been 6 speeds, so I don't know, but given how fast these things plug the radiators I thought That I'd throw that in there.

 

In order to keep my A4 cool enough on the track, my car has a B&M finned aluminum trans pan with 2 quarts more capacity, a Dewitts aluminum radiator with trans (and oil) cooler, a Derale 180 degree trans fluid thermostat and an 18" x 7" x 1-1/2" auxiliary trans cooler ahead of the radiator.

These improvements will keep the trans fluid to 240 - 250 degrees after three sessions on a warm day at Laguna Seca.

 

how to reprogramming my c5 after take off the battery?

 

Your C5 PCM has a NON VOLITOL MEMORY. Once its flashed, it cant be erased or change without aftermarket hardware and software. Just disconnecting the battery does not effect your PCM main programming.

However, that being said; Your PCM also has a LEARNED feature. The PCM uses the last known Idle info, Long Term Fuel Trim data and a few other emissions related data. As you drive that information will build and get stored and used to optimize your engine tuning.

The most that you will notice is maybe a little rough idle until the PCM relearns the data.

Why do you think you need to reprogram your PCM??

BC