I've got a 2007 GrandVan SXT and ever since I got it at 56,000 miles, the transmission has been overfilled by quite a bit. There were no problems with the trans, but I know it's generally not good for an auto transmission to be overfilled. Being pretty lazy, I figured it had been that way for a while, so I would just drive it and check occasionally, and maybe the level would go down in time. Now, 40,000 miles later, the level has not gone down one bit. I feel like I should probably do something like change the fluid, but it runs good now so I'm afraid refilling to the proper level might cause a problem. Anyone have any ideas on why this would have been filled so full, and is there any reason to leave it at that level?

 

Transmission is in park, hot and engine running correct?

 

absolutely, but the fluid level also shows too high even with the engine off. Level should be lower when the engine is off on this transmission, right?

 

You can loosen the drain plug on the fluid pan to get the level back in spec.

A slim possibility but is the dipstick the correct one for the van? A shop could have mixed them up.

It will read lower when cool.

 

I guess I better check the dipstick, but lowering the level is not going to be that hard, I just wonder if it's a good idea. Like, what if this transmission was slipping horribly before I bought it and they overfilled it to fix that problem, and lowering the level might bring back an old issue - any chance of that being the case?

 

Firstly, being overfilled isn't a good thing. Can affect shift patterns and can aerate the fluid. How much are you overfilled by? Can't be much.

Checking the level when hot can be tricky. What is the level on the dipstick when everything is cold like within a couple minutes of start-up. Your Owner Manual and your dipstick have instructions as to how to check the level.

As to when the engine is off, the fluid will be at or about the kink in the dipstick, i.e. higher than when operating. The torque converter affects the fluid level.

Electronic transmissions are sensitive to temperature, fluid level and fluid quality. I use Mopar fluid as I have no idea how Chrysler is keeping those ATF+4 Licensees honest. Next best to Mopar would be a major brand, not house brands, IMO. The transmission is too important to skimp on.

Here's how your transmission operates with respect to temperature and overfilling: http://www.aa1car.com/library/transm...sler_45rfe.htm
You can siphon or pump excess fluid out through the dipstick tube.

 

There's no drain plug unless it is an aftermarket installation such as a Dorman pan with drain plug or a B&M transmission drain plug kit.

For a recent fluid change on my 2002 GC Sport, I siphoned out about three liters through the dipstick tube, refilled and ran the vehicle for a few days and repeated the process. I thereby wasted a liter of new fluid but now have 5 liters of fresh Mopar fluid in the system.

A pump can be used to get the fluid out as well. For a filter change, say every other fluid change, a pan drop is required.