My son has a 98 CHerokee with 237,000 miles. I bought it used. His transmission is making a slight whining noise. I do not know if the fluid has ever been changed or not. Any concerns about having the transmission flushed and new fluid put in??

 

If its never been flushed you run the risk of ruining the trans after a flush with that many miles.

 

So, what if we just had fresh fluid put in? Again, I have no way of knowing if it has ever been changed or not.

 

Unless your just topping off low fluid...putting in fresh fluid would basically be a flush...no?

 

I honestly don't know. I'm not a mechanic and wouldn't dare try to work on the tranny myself.
I did check the fluid and it does not smell burnt or look discolored. Could the sound be something different? I think it sounds like the transmission though.

 

It could indeed, but I'm not a master of the auto trans.

 

Just draining out the 4 qts and adding new fluid and a new filter isn't even close to a full flush,come on now think. Do the fluid and filter.

 

No! No chemicals used in a flush are being put into the gut's ( so you know what i mean without greater detail) no high temp's or other gunk to really loosen everything up.

 

The correct thing to do as stated would be a trans filter, and then a flush. You have to figure the massive amount of fluid that sits in the torque converter, lines, and cooler that wouldn't drain.

With that many on the clock, I'd be hesitant. I have only seen 2 AW4 transmissions ever let go though, incredibly strong transmission. A friend and former Chrysler Dodge Jeep master tech was telling me that in 18 years, he's only ever replaced 3 due to failure.