I have my brand new 48RE in the transmission shop for what appears to be a broken stator shaft. In talking with the people that sold us the transmission, Browns Automatic Transmission in Montana, they indicated that broken stator shafts were a common problem they were seeing in 48RE - especially on built motors.

I searched and could find no discussions relating to broken stator shaft, is there another forum I should post this in?

Basically, is there an upgrade I can install when they fix it?

Peter

 

Stator shaft is not the common nomenclature we use on here. There are three shafts, input, intermediate, and output. I beat they are refering to the input shaft. Stock trucks have been know to break input shafts. If you have a tighter torque converter(TC), flexplate and upgraded valve body with increased pressure you can break an input shaft easily if pulling a heavy load. From what I have read and talked with people about is when they normaly break when the TC locks up pulling heavy or on a heavily modified truck running some high HP. My GVCWR towing will be over 20,000 lbs loaded so I was incourage to get a billet input shaft and when pulling horses you don't need to be stuck on the side of the road broke.

 

Thanks for the help. That's very helpful. I've heard the term input shaft but had not heard stator shaft before, but that's what the tranny shop called it.

This 48RE has an ATS valve body and controller and it was delivered with the TC set to lock at 27 mph and stay locked up. ATS said "That's what most people want" but it shifted like crap and was probably really hard on the input shaft. From others here I've learned to changed the programing to one that locks and unlocks the TC in each gear - but the damage may have been already done.

I found some billet input shafts - a pricey item, the shop also offers billet intermediat and output shafts - how crucial are they? The total cost is almost the cost of the tranny. The write up on the site with the billet shafts exactly describes my situation with the ATS controller. I wish I had known that before.

Peter

 

There is the input shaft and the other splined thingy is stator support or reaction support shaft. From shop statement, I would think the support started spinning in pump housing.
With stator support failed it would pull out very slowly as if in 2nd gear.
With input shaft failed, you ain't going nowhere. Neither forward or reverse. To break a 48 input shaft, you have to know when you did it. Fess up.

 

No, I wasn't aware of the failure. It was driving fine, I parked it for an hour, and when I came back it was as you described, like trying to take off in 3rd gear. The strangest thing is that once the tranny warms up to operating temp, it works pretty well.

Peter

 

Huh....First I ever heard of a stator shaft failure.

 

Well, it wasn't the input shaft, there shavings in the pan that had clogged several of the valves that were preventing the TC from filling. TC is suspectec to be dying. I'm going to try to get a triple disc TC and billet input shaft when it is all reinstalled but the shop here in California and the building in Montanta are having long discussions about who is going to hold the warranty.

Thanks for all the help.

Peter

 

Like someone else indicated the stator support failure is not the normal "abuse" failure with high level of power modifications. Sometimes things just happen and thats what a warranty is for.