I rebuilt my transmission last year. Has worked perfectly except for reverse once warm. I pulled it apart again recently to fix this issue which was the lip seals were backwards. My first diy rebuild. Not sure if this will be related but when I was wheeling transmission to put back in it slid sideways on my jack and the TC crashed pretty hard to the concrete. It is an approx 4 yr ats all-star TC. From the start after lip seal repair it has been surging in reverse. After driving for a few weeks it surged in D at a light. Started smoking really heavy until i put it in N to stop surge. Also seemed like really lagging in power after shift into 3. Monitored situation and it does it once fluid is warm. Will do it all stops in D. Will not do it in 2.

Then bad went to really bad.

Yesterday once warm all shifts felt incredibly sluggish. At a stop can barely get it going. Barely got home. I was hoping it was the filter but I opened it today and filter is in tight. Also have the retainer clip to hold it. I swapped out my solenoid pack since I had extra known working. Fluid levels are good. I have no codes on FORScan so idk what’s next.

anything else I should check before assuming it’s TC? I have an extra pump but everything that’s happened really feels like it adds up to TC. Appreciate any advice.

 

I can't see how that adds up to the torque converter. How can the torque converter make the shifts sluggish?

Get a pressure gauge and install it in the test port. It needs to be 0-350 PSI and have a 1/8" NPT thread.

 

I’m not knowledgeable on exactly how all the components work together. Rebuilding the transmission was just doing my best following directions. Why I’m so grateful when people like u have answers or guidance that helps.
I understand hooking up gauge. I’ve never done a line pressure test for a transmission. I assume idle is just parked and applying appropriate shift position. What/how is the stall test done? Thank you for some guidance.

 

To do a stall test put your left foot HARD on the brake pedal. Put the trans in gear. With your right foot plant the accelerator pedal on the floor. **********CAUTION - DO NOT HOLD THIS LONGER THAN FIVE (5) SECONDS OR YOU'LL DESTROY THE TORQUE CONVERTER!!!!!!!!!!!!!!!! ^^^^^^^^^^^^^^^^^^

After a stall test let it idle in park or neutral for at least 30 seconds before doing another stall test.

 

Ok. Sounds simple. Timing of this is unfortunate. We leave today for two weeks. I’ll post results of the tests once I can get them done. Thanks again Mark.

 

Ok. Sounds simple. Timing of this is unfortunate. We leave today for two weeks. I’ll post results of the tests once I can get them done. Thanks again Mark.

 

Finally installed gauge and did pressure test.

P idle 100 stall 150-160
D idle 85 stall 170 start few seconds dropped to 120
R idle 100 stall 150 dropped to 100
1 idle 95 stall 160 dropped to 110
2 idle 105 stall 180
after completing tests I did a few idle and stall rechecks as the P idle was down quite a bit from when I started. Consistently 20 psi lower than numbers I posted.
also very heavy smoke on stall tests especially R and D. Distinct smell but don’t know how to describe odor. Not rubber or brakes or exhaust type odor.

hopefully these numbers make sense

 

I pulled transmission today. I have the pump out and am going to rebuild it while it’s out. However I noticed some small metal pieces so I pulled the coast clutch out and found the frictions are all broken inside coast drum. Also several overdrive frictions outside drum are worn to metal on one side. Could this be part of my problems?
Very possible I didn’t seat the coast clutch properly when I recently addressed reverse clutch seals. I just rebuilt entire trans last year. Hoping I don’t have to pull everything but am I too hopeful it’s just coast and overdrive ?

 

When you're that far into the trans it doesn't make sense to leave the rest alone an not inspect it.

 

That’s fair. I just didn’t want to create more issues as I’m dealing with these new issues likely from failure in putting it back together properly after repairing reverse seals.