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A Transmission Rebuild as a Measure of Preventative Maintenance?

Hello people of cartalk.com,
I am the owner of a 2003 Jeep Grand Cherokee with nearly 230.000 miles on the clock. The car has always been great to me and I have over the years never skimped on maintenance or quality parts. When it comes to the transmission, I bought the car with 90000 miles and had the transmission flushed at 105000 miles and 155000. Two years ago I started noticing my transmission shifting somewhat rough when reversing out of a parking spot and shifting back into drive. It literally kicks into gear and gives me good kick in the seat of my pants. I try to baby the car by coming to a full stop, shifting into neutral and after a few seconds pause carefully shifting into drive – it still bucks like a mule at times.
Another way it is acting clumsy is at a shift point at around 30mph. I’m assuming this is an up-shift of the transmission into a higher gear and again it engages the gear with a hearty clunk. This will happen more frequently and more severely as the weather gets warmer…and we have a long, hot summer here. The commute home, dashing from red light to red light is something I’m beginning to dread for worry that it’s doing bad things to my transmission. I have since I’ve first seen these problems taken the car in to a traditional transmission shop at 185000 miles and 205000 miles to have it serviced by dropping the pan and replacing the filter and fluids but it only helps things out for a little while. As a car owner who is most interested in keeping his car dependable and getting many more years of service out of it, is this something I should caulk up to its age and call it, shall we say, less refined? Or are the symptoms I described indicative of problems to come and would a transmission rebuild be in my interest to head off any major problems before worse things happen? The Jeep is a 2WD Grand Cherokee with a 4.7L V8. As I understand it has a 545RFE automatic transmission.
Any recommendations to keeping my car in tip top shape? Thank you for your input and wisdom.

You probably have no idea how the car was treated the first 90,000 miles. Flushing the transmission often does more harm than good. We always recommend, where possible, dropping the pan and changing the fluid and filter. At this mileage your transmission has probably limited life left. You may likely need a rebuild in the next year or so.

Having said that, take it to a good independent transmission shop (NOT a chain like AAMCO, or other) and get a professional opinion. If that shop want to FLUSH, just leave and go to another one that will at least drop the pan and change the fluid and filter. Don’t go to a dealer; they usually don’t know anything about REPAIRING a transmission; they usually replace under warranty, or subcontract the work to a good independent.

You might get your shop to closely inspect the mounts on the engine and transmission and the hanger bearing if there is one. Some of you symptoms are indicative of drive train motion. And as for having the transmission overhauled as preventative maintenance, I would never advise doing that unless the need to schedule downtime is critical. And I agree that dropping the pan and replacing the filter is preferable to flushing but so far your efforts have been quite successful so more power to ya.

@Docnick - Couldn’t have said it better.

Find a good transmission shop. The local one near me…has 10 bays…and they do a lot the tranny work for the local Toyota, Nissan, Honda and Ford dealers. Dealers don’t like tearing into an engine or tranny. Far easier to send it out…or put in a new one.

Are you sure the rpm’s are dropping to around 700 or so when shifting into drive from reverse or neutral? The hard shifting could be a need for a rebuild job, but it could also be the wrong transmission fluid was used when the transmission was last serviced.

Perhaps you should have a Jeep dealer do a transmission service and see if that helps the shifting. At least then you’ll know the correct fluid is in the tranny.

A rebuild is going to cost the same whether you do it as PM or wait until it needs it. I agree with the above, mounts, new fluid etc.

I don’t disagree with the others. I would not flush a transmission. I did a rebuild at about 350,000 as a preventative measure because I was driving all over the state of Minnesota in Summer and Winter. I did not want to break down 400 miles from home. The guy said it didn’t really look that bad. Since you are having symptoms, I wouldn’t hesitate get it done if you are planning to keep the vehicle for a while. If you don’t mind getting stalled out of the blue some day, then no rush. I would also consider the factory rebuilt or new transmission instead of a local rebuild. Then its just R&R and factory fresh. It’ll cost more but with a longer warrenty.

If you get the transmission serviced make sure they replace both filters. Besides the sump filter the 545RFE has a spin on oil cooler return filter next to the valve body.

As was already stated, the cost of a trans rebuild will be essentially be the same, whether it is done proactively or as a result of trans failure. The only differences will be in terms of convenience and (possibly) paying for a tow.

So, if this Jeep is the OP’s only vehicle, and is needed for daily transportion, it might be a good idea to be proactive with this issue. But, if the potential inconvenience of breaking down in an unknown place–at a bad time–is something that the OP does not fear, then it might make more sense to wait until the trans actually does stop functioning. Personally, I would do a “normal” trans fluid service at this point, and then wait for the inevitable.

I have to disagree with some posters here. A good transmission shop will rebuild YOUR transmission rather than replace it with a rebuilt unit. The cost to rebuild YOUR well kept, well serviced transmission may be less than a rebuilt unit that has the average “run it 'til it pops” transmission that ends up at the mega-rebuilder’s shop. I’d say the OP would be well served to get it rebuilt now before it wears further and starts really tearing up the internals.

A good transmission shop will rebuild YOUR transmission rather than replace it with a rebuilt unit.

Go back and read the posts…Everyone said that a transmission shop would rather rebuild the transmission…But DEALERS do NOT like to rebuild. They either send it out to be rebuilt…or they remove/replace with a new one.