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100K miles Transmission Service

I have a 2005 Chrysler T&C minivan with almost 100K miles. I’ve never had the transmission fluid replaced. It run great and I’ve had no problems. I’d like to keep it another 100K. Should I have the tranny cleaned and filters replace?

Sure. You’ll get a few here that will say “don’t do it, you’ll destroy your trans”, but it’s bunk. The myth starts when someone waits until there’s a problem, changes the fluid in a prayer that it corrects the issue, the trans goes from the original problem …voila~ …the fluid change destroyed the trans.

I’d recommend buying and using Auto-Rx before a full fluid exchange. Now I’ll further preempt the novice:experts …an EXCHANGE is not to be confused with some FLUSH where some solvent chemical agent is used in the process. It simply exchanges new fluid with old fluid. Auto-Rx is just a metal cleaner. No solvents in it. You drive it from 600-1000 miles before the fluid exchange.

Not knowing your trans in particular, there may be some altered shifting until the TCM readjusts to the newer and higher visc fluid. I’d consider a synthetic AFT like Amsoil or maybe Mobil 1 …but any +4 will do fine.

You can do this yourself if you can reach the cooling lines easy enough. You can even make the pan drop less messy. Before dropping the pan, unhook the cooler line. Have a piece of 5/16 cooler line to attach to the fitting you took the OEM hose off. Place both in a gallon jug. Start engine. When bubbles appear, shut off engine. Now you remove the pan, clean it out, and replace the filter. After you button it up, fill with 2-3 quarts at a time and repeat the process. You’ll naturally have to empty the jug twice. After you’ve added about 8-9 quarts, hook up the lines and top off. Run for a bit and check the level. Drive until warm and recheck the level. Then check in a day or two. Without the pan drop this takes about 10 minutes.

Good luck.

The issue is “how to clean your tranny” at this point. Changing filter and fluid every 30K miles is best. That’s not the case here however. Do NOT have your transmission flushed by any of the quick lube or chain tire service facilities. A badly done flush can cause problems. Quickie places hook up the machine and do the job quickly without removal of the old filter or cleaning the pan first. This just circulates the crud under pressure and can cause more problems than it solves.

You are not having a problem now. So, one option is to go to an independant transmission shop and have the pan dropped, cleaned, a new filter put in and refilled with the fresh and very important correct fluid. Sometimes a dealer is the best option for this service, the dealer charges more but you can be sure to have the correct fluid in your transmission.

If a good independant trans shop flushes your tranny just make sure they do the pan drop and clean and use a new filter. A properly done flush should be OK, and still important to refill with the correct fluid.

Many folks report issues after a trans service and it is either the trans was shot first and they hoped the service would resolve the problem. Or, the flush was done incorrectly, and finally the fluid used to refill the trans was “generic” and not specific for the transmission. There are now many types of fluid and sometimes the dealer is the best source of the correct fluid.

Just have it drained & replaced with OEM fluid and the filter replaced. No big deal.

I agree with draining and replacing the fluid and filter. Never FLUSH a transmission.