I have been having some problems with what I think is my transmission lately and need some advice. I have a 1999 Ford Mustang GT with automatic transmission and about 145K miles. I bought the car at 80K and have not had the transmission serviced at all.

When the car changes gears, occasionally there is an audible noise and the car rumbles. It feels as if the rumble is coming from the transmission. I know it is not an engine issue as I recently had the engined tuned and had a piston that was misfiring fixed. Has anyone had this problem before or have any recommendations on what to do?

I have seen a few people in other threads recommend that a fluid change could fix the problem. When I talked to my mechanic (I am newly going to him so am not sure if he is trustworthy) he recommended a flush. I have heard a lot of mixed opinions on flushes and am unsure what to do?

I need some advice! What do you recommend?

 

I have been told that is a sound from the tranny. A flush will either help it or you need a rebuild anyway. I would do a service at a quality shop and see what happens, expecting the worst.

 

I've allways been told that if its not been flushed in the last 50k leave it alone, but it seems like you may have bigger problems anyways so it might be worth the $100 to do it

 

Change the filter and fluid. check the tranny mount and every part around that area that will/ can cause a noise.

 

First things first, check the transmission fluid, Smell it it should be bright red and clean looking. If it is brownish and smells burnt, i would then move on to replacing the fluid and screen/filter and then see if it acts any better.

 

Yank it and put in a stick shift. Less **** goes wrong

but like the others have said, a flush cna't hurt but it sounds like the issue is bigger than what a simple flush will do

 

^^this^^ as well as check ujoints and rear pinion bearing for any kind of play . A problem any where in the drive line can travel though the drive shaft and appear to originate from the trans.

Generally when an auto trans starts to go it just slips or wont shift .

 

Thanks for all of the input, guys! I got a fluid and filter change and it seems to have cleared it up. I've put about 70 miles or so since then both city and highway and it seems fine. Thank God! I think I may have dodged a bullet there.

 

Glad it worked you for you.

 

I had the same experience this past Summer.
Rumble on downshifts at 109K.
Likely no previous service.
I took it to a shop that is family owned since 1951 in Waukegan Illinois:
Karry Brothers
I was informed that it may or may not fix the problem, but fortunately it did the trick.
Anyone local to the Chicagoland area would do well to have transmission work done by these guys.