I should know this....but I am doubting myself.

I have recently moved from WI (VERY FLAT) to Pittsburgh (QUITE HILLY) and I have been using my transmissioin to control my speed when decending hills. I am under the impression this will not cause any long term issues with the transmission, am I right?

I have not been manually shifting when climbing hills, although I do frequently turn off the OD - same question, any issues if I were to manually shift to control acceleration when going up?

My concern is long term wear or issues and if I should change out fluid more frequently due to this technique.

Thanks!

 

I don't think so, but I'm sure some experts can confirm or deny.

I've lived in PA my whole life, and a lot of people here downshift their autos on hills. I too have turned off overdrive in the past as well.

 

I have noticed on mine it will downshift automatically to control downhill speed when cruise is on. I believe it does it from O/D to 3rd.
I have done it manually from 3rd to second when not going too fast.

O/D can be off all the time with no ill effects.
When downshifting manually, make sure you are at a speed that won't over-rev the engine. Sometimes I have used the brake to slow down, then dropped it down a gear.

 

As ronjenx said, make sure you are at a speed where it won't over rev the engine. As long as you stay in the RPM band, you should be fine downshifting. It won't hurt anything. The selector lever gives you the ability to select a gear (or, more appropriately, restrict the transmission from shifting above a selected gear) for a reason - to control the transmission in instances where the programed shift points make no sense, i.e. controlling speed or keeping the rpms up on a climb.

 

That right there is the point I have tried to make in the past, but did not word it so perfectly.
A lot of career automatic drivers have no idea what the selector lever can be used for. I say this more about the average driver, not most Jeep drivers. Those who drive auto Jeeps usually find out off road the importance of the transmission selector lever.

 

Just had to quote you because that's how I found out it's purpose: during steep descents, slippery descents, etc.

 

I do know some transmissions are designed to be shifted manually (eg. the Tiptronic). I am not familiar with the internals of the JK's auto, so I am by no means saying this will happen.

A few years while driving cross country towing a trailer with Chevy PU in steep terrain, a friend decided to manually shift his auto. After about 6 hours of doing this somewhat regularly the auto started shifting very erratically. As it turns out the repeated manual shifting wore out some sort of nylon cam or gear inside the transmission. The part was cheap, but the labor about 4 years ago was ~$400 at the stealer.

If you want to do this on regular basis, consulting a transmission specialist (maybe someone in this group) may save you some pain.

 

trade it in and buy a manual, way better here in pittsburgh

 

The part was most likely ready to go anyway. Could have been a defective part. How many on the tranny? A 6 hour trip wouldn't wear out a part unless it was worn already.

By 220,000 miles lots of transmissions get replaced. Mostly because of neglect.

 

its called an auto for a reason. leave it alone. using the tranny to slow down is ok but you are working it harder. brakes are cheaper and can be done at home.