I've noticed a few times in the last week that my transmission is making an odd grinding noise occationally. It'* happened when I'm accelerating from a stop usually and the engine is at about 4500 rpms and then I take my foot off the gas or decrease how much gas I'm giving it. The grind seems to sound with a shift that'* occuring at the same time I decrease the amount of gas I'm giving the car.

Any ideas?

Trans shop for estimate would be your best course of action.

Sounds bad and the free estimate is your friend.

You think they'd be able to get a feel for what it is without taking it apart?

It doesn't happen all of the time and with my luck they'll drive the car and it won't do the noise, just like last time I took my last car to the shop for a transmission problem.

Hows the reputation of these transmission? It'* a 4T65E, right? I think I had the 4T60 in my Lumina and I that thing just couldn't be killed.

If you take it to a good local tranny shop, they may have run into vehicles with similar symptoms. What they tell you will be an educated guess, until they tear it down.

How many miles on the car? Has the fluid and filter been changed? Old, funky fluid can cause strange problems. Any shifting problems?

No, i don't think I've noticed shifting problems other than just that noice thing.

I've currently got 87,xxx miles on the car and I have not a clue if the fluid and filter have ever been changed because I bought the car with higher miles on it.

You could try replacing the fluid and filter first, and see if things improve. However, generally noises from the transmission indicates something more serious than old, worn out, fluid.

yeah, I was thinking about changing the fluid. Unfortunatly I have to get a shop to do it because of my warranty, so I'll start looking for prices.

My Bonnie is sitting after making the exact same noises as yours. $2K-$3K after install dep on where I take it to rebuild. This is the tranny our cars should have been "married" with --> http://www.transmissioncenter.net/alto_2.htm
Putting these stock plain jane trannies in a supercharged car is insane. Of course if they did have the HD transmissions like the one below, no one would ever have to repair them so GM and the tranny shops would lose money



Anyone know where I can get a similar tranny like the one above for less than the $2500+ they want? At that price I guess I could buy 3.5 rebuilt stock trannies.

Also on the list for repair are some common and not so common problems (Driven 12 mo and 20K before problems started appearing at horriffic rates). Mileage is 142,000km (not miles). Yes the guy that got rid of it before I bought it did so at the best possible time for him I guess...

1) Driver side door module or the like fried. No power to all doors except drivers side (no one seems to be able to figure this one out incl 2 mechanics that had the car for 3 days). Car "boots" them out of diagnostic checks and sends back no codes)
2) Leaky trunk
3) Leaky rear door (floor gets soaked). Probably caused problem #1 by frying electonics under the seat (Great place to pu tthem).
4) 2 rear shocks leaking (car sways badly when going over bumps at higher speeds)
5) Lower intake manifold gasket (currently a class action lawsuit regarding these parts isn't there?)
6) Drvier side seat heating kicks out intermittently.
7) Wheel Speed sensor and hub

Doesn't seem bad right? Pretty much all the problems above sppeared within 3 mo of each other, among numerous other noises just starting to appear from the front end

REPAIRED: Both rear door regulators as per the instructions on this site (very helpful and cost me $0.00 saving me money for the numerous "real" problems
Many other little things. My car is a money pit, hopefully yours won't be. We do not abuse or drive it hard (before you ask).

Bottom line is these cars were built around GM'* best V6 engine ever built, bar none but it seems the rest of the car was engineered by 5th graders (or mickey at Disney)

I dont think 3.5 stock trannys will compare to the performance ungrade you would do with 1 severely upgraded trans. you could have a good friend that knows trans' do it, or rebuild it yourself, which most people cant without help, including myself, could be a good learning experience. I was looking into a Raptor 4L60E for my Yukon. I was totally prepared for the price, cause performance= $. But ended up not keeping it anyway. Maybe find a good trans shop, get a lower mile junker trans, go through it/replace hard parts that might be messed up, and have them rebuild it with all performance parts you want.
Here are two other ones I found for ya. I dont know of the dependability of the people building them though.
http://www.modbug.com/trans.html

http://www.thrashercharged.com/store...rans_group.asp