I know there are a lot of threads on transmission slippage, but here's my problem; my 2003 A6 4.2 with 145.000 miles slips into third, doesn't fully lock, and then shifts to fourth. It is most noticeable under hard acceleration and funnily enough, it shifts better when the car is cold. All the other gears shift fine, and in tiptronic/manual mode even third shifts fine. There are no codes, and the fluid level is normal. From what I have found out so far, this sounds like a valvebody. Any ideas?

 

It could be a valvebody...It's likely 3rd gear gets the brunt of abuse during hard acceleration and is very worn. My S4 v8 Avant would pull over 100mph in 3rd (manual trans).

The reason it shifts better when cold is that the ATF fluid retains more viscosity and is better able to support the clutch packs and provide necessary friction. When hot the fluid thins out and is the oil' shear strength is reduced.

If the fluid and filter has not been changed in a couple years do it ASAP. Most trans seem to fail in that mileage range, no matter the brand. I've yet to see a failure that wasn't due to neglect or lack of maintenance; see "neglect". I know Audi and BMW have "lifetime fluid" in the trans....seems that lifetime is coming to an end, unless further action is taken.

If it is a valvebody, it's more likely contaminated with debris (see above comment), than an electrical problem, otherwise there should be code. The debris will prevent full flow to the clutch packs which prevents full clamping force to lockup the gear.

Either use the OEM synthetic Castrol fluid, or upgrade to Amsoil ATF, which is better and likely much cheaper.

You can buy it here: http://www.synthetic-motor-oilsite.com/1688537/

Just don't use regular ATF, unless it's for flushing out the trans, still not recommended, but it's better than old contaminated OE fluid.

I recently serviced a 2002 S8 and it takes almost 10 quarts. Amsoil ATF was used. If you do not have a ATF fluid exchange machine, for a drain and refill service it will use only about 5 quarts. This is not adequate but will help and maybe even "fix" the problem. Don't be lulled. I would recommend to do another drain and fill, but leave the new filter in, within 1,000 miles. You will then have about 75% of the fluid changed, since only 50% drains out.

If a shop has an fluid exchange machine you will need more fluid, get at least 15 quarts (17 would be best), as the machine requires some fluid in the transmission to work (at least our does). Overall money well spent to save a very expensive tranny. Good luck!.

 

You need to post in the A4 forum, not just anywhere and totally remote from someone's problem topic.

 

It was an accident. But thanks for pointing out the obvious, a fine job, lad.

 

Thanks a lot! I am gonna have it done first thing mondaymorning, I hope I can save the tranny...

 

Good thing it was so obvious you caught it right away....

 

Actually I did, but the silly forum times out so quickly it didn't update. Keep up the good job of pointing out mistakes, I'll keep doing my best to actually help people.

 

Actually I pointed out the mistake just TO HELP YOU, not to mock whatever you posted. And even if an A6 owner might have a nice A4 for your liking, you should have still inquired as a new thread, not "jamming" someone's transmission problems post.
I think that's the obvious you're referring to.

cheers 2U2

 

HAHAHAHAHAHAHA....okie dokie. I'll do my best not to point out what a smart *** you are in the future.

 

I'm sorry, but exactly what involvement do you have with this?..? Aside from being antagonistic.

Maybe, You should try harder--to help someone solve a problem (like I have tried, in this post, no less).

Should we have a talk with the Admin about your personal issues about pointless and insulting attacks?

Jurrien28:
I am sorry you have to deal with these childish antics. As you can see there is a reason why my posting count is so low over the years. I hope your trans is okay and that my advice proves helpful and correct.