Tranny still has same problem....

[StewartFan20]

Sorry, I couldnt locate my original thread so I will sum things up again for anyone new to reading this. I have a 91 grand prix, 3.1v6, with the 440t4 4t60 tranny. When driving it, the transmission sometimes hesitates downshifting into 1st gear. It doesnt do it all the time and it sometimes may only do it once or twice during several hours of driving. The best way I can describe what it does is like say Im coming up to yield and turn right onto another street it will not drop into 1st and the motor will rev up of course as if it were in neutral then after a couple of seconds at idle it will bump down into 1st and go on my way. I have already replaced the fluid and filter although the fluid still looked good, and I have also replaced the vacuum modulater. I have access to another tranny just like it for parts if I could just figure out what it needs. If its the tranny itself I will just swap it out but I really hope thats not needed. Any other ideas anyone?

[maxwedge]

If this only happens in a turn, try adding 1 qt to the trans fluid.

[richtazz]

Or, if it's a sticking valve in the trans, instead of adding another qt of fluid, try adding a trans additive like Seafoam or Trans-X, which would help both a low fluid level, which Maxwedge was adressing, or a sticky valve.

[maxwedge]

Originally Posted by richtazz

Or, if it's a sticking valve in the trans, instead of adding another qt of fluid, try adding a trans additive like Seafoam or Trans-X, which would help both a low fluid level, which Maxwedge was adressing, or a sticky valve.

Good idea Rich, tried bottle of Lube Gard red in my high mileage 98 LTZ 4t65e, with a 3/4 slight flare did seem to help some, he may have to add about a pint more after the Seafoam, though.

[StewartFan20]

Well, I finally gave up and went to a local tranny shop and the owner took me over to a 4t60 he had on the shelf and showed me where the speed sensor was located. He said its uncommon for this tranny to act up on downshifts when this part starts to fail but was most likely gonna be the problem. Long story short, I took one off another tranny I had and installed it and it worked!! Just thought I would share that with the board in case anyone else has a similar problem maybe it will keep them from what I was doing----->

[troy1]

The old 440's have lots of problems. Most of the revolve around lube issues. It could be the sprag not able to hold properly anymore. What happens when you manually pull it down into first when is does this. does it instantly go into first or does it still neutral. oh well I'm late I see but good info anyways

[StewartFan20]

When I shifted it manually, it always went right into gear. ohh, and YES the 440's have trouble. Ive been the unfortunate owner of 3 cars with them. All 3 have had problems of some sort and one had to be totally rebuilt a few years ago. I have lived and learned about these trannys....lol....I will be sure to look under the hood of the next car I buy and be sure its not a 440t4.