No forward gears, but revers works after loud clunk at nearly WOT.

Hey folks, been busy lately and not much time for my favorite forum. I’ve been maintaining my ‘03 and trying to keep her healthy. So I just had a mishap. Taking off from a stop, probably 70-80% throttle, and I’m not sure if it was on the shift from 1-2, but believe so. Loud clunk, and now I have only reverse. Manually shifting into gears also doesn’t change this. Fluid is full, and still a little red. She’s due for a change. I have the Performabuilt level 3 transmission, and certainly didn’t expect to have a failure without some significantly higher horsepower. I have terrible internet right now, so doing a quick search I didn’t find a match to this issue but may have missed it. Apologies if so.

Sounds like the tranny is gone, how long have you had that transmission? I've seen several videos from performabuilt and not sure I agree how they rebuild their transmissions. They don't upgrade all the components that are known to fail.
What is the warranty those guys offer?

Yeah, I chatted with them a bit and he believes the forward sprag is failed. I’ll be pulling this one out, and packing it up to ship to PA. Good that I have my original here for a spare, but definitely not looking forward to doing the work. Sounds like the forward sprag is not a common failure point, but I don’t know if that is an upgraded component or not. Transmission is 2 years old and approximately 30k miles.

@NickTransmissions, opinions?

Forward sprag or low roller one-way clutch. If you have no forward movement in manual low then low roller has failed (these dont go bad very often). If there's movement in manual low and 2, but not Drive then fwd sprag. Borg Warner makes both and a new one of each should have been installed.

Sam Harris said:

Hey folks, been busy lately and not much time for my favorite forum. I’ve been maintaining my ‘03 and trying to keep her healthy. So I just had a mishap. Taking off from a stop, probably 70-80% throttle, and I’m not sure if it was on the shift from 1-2, but believe so. Loud clunk, and now I have only reverse. Manually shifting into gears also doesn’t change this. Fluid is full, and still a little red. She’s due for a change. I have the Performabuilt level 3 transmission, and certainly didn’t expect to have a failure without some significantly higher horsepower. I have terrible internet right now, so doing a quick search I didn’t find a match to this issue but may have missed it. Apologies if so.

Click to expand...

NickTransmissions said:

Forward sprag or low roller one-way clutch. If you have no forward movement in manual low then low roller has failed (these dont go bad very often). If there's movement in manual low and 2, but not Drive then fwd sprag. Borg Warner makes both and a new one of each should have been installed.

Click to expand...

Thank you for the info. I was getting a small amount of “clunk” when dropping all the way down into 1st, but still no movement. Now, I get absolutely nothing in any gear manually, or in D, other than reverse which thank God allowed me to back it into the shop. Got a lot of work ahead of me. Appreciate the information very much!

Sounds like the transmission is toast. When mine failed, it went out in a similar fashion. I could only drive in Reverse, or in 1st gear. And i couldn't go any more than 15-20mph. Thankfully I was able to limp it home like that, as l was less than a mile from home. When I had it rebuilt, they said my sunshell was busted as well as a few other hard parts, but the clutch bands actually didn't look too bad for a 4L60 with 150k miles on it. I had another failure about 4 years later, which wasn't under warranty, but the shop took care of me anyway since it only had 41k miles on it since the rebuild. It was some sort of bearing failed, l forget the exact name of the part. But he only charged me for parts, NO LABOR. It was less than $200 in parts, and he pulled the transmission, tore it down, replaced that bearing and put it all back together and re-installed it in my truck. Most shops wouldn't even pull a transmission for $200, let alone rebuild it and reinstall it!

Sam Harris said:

Thank you for the info. I was getting a small amount of “clunk” when dropping all the way down into 1st, but still no movement. Now, I get absolutely nothing in any gear manually, or in D, other than reverse which thank God allowed me to back it into the shop. Got a lot of work ahead of me. Appreciate the information very much!

Click to expand...

You're welcome, Sam...

ScottyBoy said:

I had another failure about 4 years later, which wasn't under warranty, but the shop took care of me anyway since it only had 41k miles on it since the rebuild. It was some sort of bearing failed, l forget the exact name of the part. But he only charged me for parts, NO LABOR.

Click to expand...

I do the same for my customers if they have a fluke failure like yours after overhaul...I only do bench jobs so they'd bring back the transmission to me and I'd deal with it...The customer pays for parts, labor is on the house.

Good Luck, Sam.

I sure don't envy you Sam. Pulling and reinstalling a trans isn't easy. Hopefully you have some help lined up.