4T60-E Problem

[dk05]

Well, I think my tranny is on the verge of being toast. Today when I was driving I had to rev my car up to 7000 RPM's to get the thing to lock up because up til 7k it would not do anything at all! I have had problems with the tranny since I have gotten it, supposedly it only had 29k on it, but I doubt it. Before today all it was doing is grinding, which I posted here a couple times asking about it but nobody seemed to know what was wrong with it. It sounded like the one service bulletin that I read on this site where it made a grinding noise on cold start, but it did it all the time while I was driving, and now it takes 7000 RPM just to get it to lock up. Anyway, my question is, is this a good sign of failure? Also if I get a rebuild kit with the clutches and everything, would that be enough to fix it, or could the torque converter be bad and maybe my only problem? Thanks.

~Dk

[Kevwood]

Hmmm, your car must have a chip eh?

[dk05]

Hmmm, your car must have a chip eh?

Actually... no.. no mods on the car yet.

[Kevwood]

I ask because you say you are have to rev up to 7K, my auto had a shift point at 6250, we then changed the shift points in the ecu to shift at 6500 and then eventually into the 7K's.

[dk05]

I see... the problem is though, it just is not grabbing. It is actually more of an accident that I rev to 7k then I let off and slowly hit the gas and it grabs at about 1.5-2k it is a very odd problem.

[GPSonoma]

I'm no transmission expert, but maybe a valve in the trans is sticking, and the 7K rev causes the pump to build up enough pressure to free it. If it were me, I'd have the trans fluid flushed and see if it fixes the prob. It's not cheap, but it's cheaper than having it rebuilt or replaced.

[RednBlack]

Does it whine on cold start?

[torq455]

the quick little growel you hear at start up is the pump cavatating. gm says this is normal due to the fluid draining out of the pump. mine goes away after a second. if you have grinding in D or R, you may have a 97 or eariler tranny that dosen't have a hardened shell. these will wear the ends (point of contact) off, and the grinding is the metal scraping on the case. if the shell goes you will only have 1st gear. maybe your pump has low pressure. ummm little off subject.....i took mine in for a winning/grinding sound spent 1k on it and it was bad bearings in the water pump. just food for thought. a flush and a filter is the cheapest place to start. good luck!!!

[sharkey]

a flush and a filter will not fix it. changine the oil wont put the friction material back onto the clutch plates, it wont put teeth back on broken gears, it will not replace the brass on bushings and thrust washers. and if ychanging the filter fixed the problem, your old filter is plugged full of most of the tranny and your not gonna get far before there is nothing left of anything.

saying doing a tranny flush will fix a major problem is like telling someone to change their engine oil to fix the hole in the block from were the connecting rod went through.

[sil]

sounds like it could be torque converter internals, bearings went maybe and its sloppy, so the vans are grinding inside
could also be sticky modual, take it off, get some needle nose pliers and grasp the plunger and move it in and out and see if its sticky

run the car in park, and pull the fluid checker and get some white tissue and wipe the dipstick on it and let the capillary action take place :P see what colors there are and if there are little metal shaving, take a magnet to them if you got enough and see if they are magnetic if not then its aluminum and your pump cover/vanes are grinding.

there is what looks like a bolt on top of the tranny undo that and put a hydrolic pressure checker on there, refer to your manual for pressure check, that will tell you if your pump is bad as well