Hi all..... RED 2000 C5 Corvette: Automatic, 149,000 miles

Just replaced my Rack and Pinion steering system, along with Harmonic Balancer, Torque Tube, Radiator, transmission cooler, AC actuators, all belts and some coils. Now the new torque tube is in, and it has been running fine for a few weeks, but now, my transmission seems to be slipping when I accelerate, but not always until she is hot. I had early signs that something was wrong when I put her in reverse it took a few seconds to engage to begin reversing, I am hoping it just running low on transmission oil for some reason. I have spent roughly $7,000 on this car and would hate to rebuild the transmission at roughly $4,000.

Is there a post to check the trans oil, or properly fill the Transmission?

 

Step 1 verify trans fluid level. There's no dipstick on a c5 auto so you pull the fill plug and stick your finger down in the hole. The fluid should be about to run out of the fill port when the car is level on 4 jack stands. If it's too low you most definitely risk damage to the clutches.

Step 2 how often has the fluid been serviced? 4L60E is not a particularly robust transmission even if you take good care of it. If the fluid smells bad or is real dark that's a bad sign. It's probably time to have the fluid properly flushed and see if that helps. DO NOT believe people when they tell you "changing the fluid will finish it off" because its patently ridiculous. If a transmission is already bad and you change the fluid and it dies, it died because it was already bad NOT because you changed the fluid. Period.

Good luck let us know what happens.

 

There is a specific procedure for checking and filling transmission fluid on this car.
The car must be level and running with temp around 105 degrees to check for the proper level. When you reach this temp you remove the fill plug and add fluid Dex III until it trickles out.
DO NOT SHUT THE CAR OFF until you have that fill plug in tight.

 

Thanks will keep you all posted

 

Thanks will keep you all posted

 

Yes, you should first check fluid level. Following is a procedure to change fluid and filter as well as check fluid level.

Changing the fluid and filter on a C5 A4 is fairly easy, but there are specific procedures to insure that the fluid level is correct after the change:

With the car raised-

After replacing the filter and bolting the pan back up, fill with new fluid to the drain/ check level plug hole. Then start the engine and leave it running with the transmission in PARK.

Immediately add fluid through the drain/ check level plug hole until fluid flows out of the plug hole. It may take as much as another couple of quarts.

With your foot holding the brakes, cycle the transmission through all the gears, then back to PARK.

Go back underneath and make sure that fluid is still dribbling out of the fill/ check level plug hole. You might have to add some.

With the engine still running and the transmission in PARK, monitor transmission temperature on the DIC. When transmission temperature rises to 122 F, put the plug in the fill/ Check level hole. Keep a pan under the hole, fluid will dribble out as the transmission temperature rises.

Do NOT shut the engine down until the plug is in the fill/ check level hole. If you do, HOT fluid will gush out and the transmission will be low on fluid.

I recommend full synthetic fluid.

Keep in mind that the above procedure drains about half the fluid in the A4. The other half is in the torque converter and other works.

You will need a small hand pump to pump the fluid into the fill/ check level hole.

 

I put in 2 qrts of DEX 4 synt transmission oil into the trans using the above procedure. bBy

Not that hard just have to be careful.

It is a lot better when I drive it in gear 1,2, 3 but when I put in automatic it pops out of the gear and does not change gears timely and it also jumps back into gear...

I love this car, but I am not sure I am pouring good money after bad? May be

I am told a new trans will cost me 4K plus installation.

By the way, the shop put in a new transmission cooler, could this be the source of the problem, like an airlock or somthing. I noticed that the color of the old transmission oil was dark and not bright pink this time? Note- When I changed it 100K is was still bright pink.

HELP! thanks

 

4k is way too much, you can buy a level 4 built transmission from RPM for $2295. A rebuilt stock transmission for half of that. Plus installation. Shop around.

 

I'm having a hard time following your timeline regarding the fluid condition. You note that the "old" fluid was dark "this time" - do you mean it was dark when you recently put in the two quarts of fresh fluid? And it was still red/pink when the shop installed the oil cooler? Dark fluid typically indicates damage to the transmission clutches or possibly the torque converter lockup clutches, if that occurred (along with the symptoms you're describing) it could be that the shop didn't get the transmission full after they installed the cooler, and since the fluid is what lubricates everything inside the unit that could result in overheating and clutch damage.

One thing you could try before throwing in the towel on the transmission is to siphon enough fluid out to allow putting in a bottle of LubeGard (the red bottle version). The valves in the transmission control unit/valve body have fairly tight tolerances and any small amount of debris (that could have been introduced when the cooler was installed) can cause the valves to stick - when I owned several transmission shops that would occasionally happen after a rebuild and in most cases putting in a bottle of LubeGard (which has really high tech lubricating properties) would free up the valves and the tranny would work perfectly. Won't help if there's internal damage but might be worth a bit of time and effort if that's not the case.

 

So, I am wondering if the shift cable bushings might be failing, not putting the transmission all the way into drive. The rear cable bushing is fairly easy to see with the car raised. If it is loose or obviously deteriorated, the front one may be also. The rear one, though is above the exhaust pipe on that side and more subject to heat related deterioration than the front one which has the tunnel plate below it for insulation.

If the rear bushing is deteriorated, replace it and see what's up. If that solves the problem, you should plan on a shift cable change or disassemble the console and shifter to replace the front bushing.

 

I hate to say it but this isn't how a transmission works. The transmission can't be partially in drive. If the fluid was low, and is now dark and smells bad and its slipping and not shifting right, then the clutches are smoked and it needs to be rebuilt. I'm also worried about what another poster above mentioned that the shop that added the cooler may not have properly filled the transmission afterwards. Very disturbing indeed....but luckily as was mentioned 4k is not a good price at all.

 

The transmission is finally replaced at a local shop in Honolulu for $3,275.00, it is running, but now I think my power steering is leaking from the fitting where the fluid comes from, or i have hole in my transmission line near the power steering pump under the front leif spring.

So after 7 months now this is where i am at........

1) New transmission $3,275.00
2) New rack and pinion
3) Two new fuel fuel pumps
4) Refurbished Torques Tube
5) New Harmonic Balancer
6) All new belts and tensioners
7) New Rear swaybar bushings
8) New Radiator
9) New trans Cooler
10) New actuators, still getting codes, but low nice and cold
11) 4 new tires
12) New schocks
13) 2 hew coils, and 8 new spark plugs and cables
14) about a year ago had the main seal replaced and I think it is whining again
. when I take my foot off the gas the whine stops.
15) New LED DRL's
16) New brake shoes about a year ago

So I am done a lot of work by who is no mechanic, I am a banker, but had the shop do the very complex stuff that required we drop the Torque Tube 3 separate times. So I am done. The car is now 21 years old with 149,000 miles and I lover her, but taste of constant repairs is getting old. The new C5 is too aggressive looking for me so as I approach 60 I am out. So if you buy a nice 20 year old corvette be ready to put your hand in your pocket. To be honest, for 15 of the 21 years I have had few problems up until she turned 19 years old. I

 

Sounds like you've had some good work done. I will say that on #14, main seals do not whine. The whine you hear is the differential gears wearing improperly. The C5 diffs all share the same failure mode that the conical spring washers that compress the clutch packs crack and allow movement inside the diff that spaces the gears improperly. The fact you got 150k miles out of the diff is really freaking good frankly.

 

Thanks much. your feeback. I have been lucky,

 

- Sorry I did not answer your post
When I went to check the trans fluid level, I noted that that the trans fluid was low, and when I did put in trans fluid what came out was not clean. there was fine dirt like stuff in the trans. That is why I took it in and got it replaced. thanks and any follow up comments appreciated.