'Change Trans Fluid'

k63d400 · #1 (**permalink**) 04-20-07, 11:19 AM

I received the 'change trans fluid' message the other day.
My brother is a mechanic and owes me a favor so he is going to change the fluid for me, just had one question.

He is going to pull the pan and replace the filters and all, should he just do the 5 qts in the pan or pull the plug from inside also and do the 11qts or so.

I ask because my car had 156k miles and to be honest i don't know if the previous owner had a trans fluid changed and I've heard horror stories about changing the fluid. Thus far i've had no problems with the transmission.

Also someone recommended Dex VI instead of III, any thoughts?

**Ranger** · #2 (**permalink**) 04-20-07, 12:36 PM

Drop the pan AND pull the drain plug under the side cover inside. No filters to replace. The two screens are reusable. Just clean them if there is anything in them. Mine were clean at 100K ('97 Deville). Dexron VI (or whatever the latest is) supersedes Dexron III so use what ever is available now.

The CHANGE TRANS FLUID message is not mileage related like the OLM. It usually only comes on if the trans has been overheated to the best of my knowledge.

codewize · #3 (**permalink**) 04-20-07, 02:06 PM

I went crazy during my rebuild and filled with Amsoil fluid. I figured if I was going to do it at all that was the time.

JCM1 · #4 (**permalink**) 04-20-07, 04:17 PM

I agree with Ranger in the draining of both the pan and the valve body. I did this job this past fall on my DeVille. I did however, replace the filters. They were not bad but, might as well. You can get a filter and gasket kit at Autozone for around $25. I did not replace the gasket as the kit gave me a cork one and the dealer put a rubber one on a few years ago when the trans was serviced. Don't forget to wipe off the magnet on the pan. I used Mobil One synthetic to replace the fluid.

creeker · #5 (**permalink**) 04-20-07, 04:23 PM

Quote:

Originally Posted by Ranger

Drop the pan AND pull the drain plug under the side cover inside. No filters to replace. The two screens are reusable. Just clean them if there is anything in them. Mine were clean at 100K ('97 Deville). Dexron VI (or whatever the latest is) supersedes Dexron III so use what ever is available now.

The CHANGE TRANS FLUID message is not mileage related like the OLM. It usually only comes on if the trans has been overheated to the best of my knowledge.

Hello Ranger,I changed filter and fluid in my 80 cdv ,6.0 litre last year ,I didn't know there was a valve body drain, would my car have this valve body drain, tnx Ken

**Ranger** · #6 (**permalink**) 04-20-07, 08:52 PM

The drain is not for the valve body, but for the side cover. Not sure what trans you have. The 4T80E is a dry sump, so the fluid is stored in the side cover, where you add the fluid. There is a drain plug below it, inside the pan that must be removed to drain the side cover.

John Wicz · #7 (**permalink**) 04-20-07, 08:57 PM

The CHANGE TRANS FLUID message is not mileage related like the OLM. It usually only comes on if the trans has been overheated to the best of my knowledge.[/quote]

Mine is at 99%, are you saying that it never decreases.

**Ranger** · #8 (**permalink**) 04-20-07, 09:13 PM

Yes. unless you overheat it.

creeker · #9 (**permalink**) 04-20-07, 09:59 PM

Quote:

Originally Posted by Ranger

The drain is not for the valve body, but for the side cover. Not sure what trans you have. The 4T80E is a dry sump, so the fluid is stored in the side cover, where you add the fluid. There is a drain plug below it, inside the pan that must be removed to drain the side cover.

Thank you