1000 FT LB of Torque

FredH · Jan 19, 2019

The 68 RFE is the transmission I rebuilt and while " Yes " you can beef them up , there are more clutch plates , planetary assemblies that are billet grade , etc.. . There are a couple of key area's that have no upgrades available . One of the main downfalls is the thrust bearings . When 1 fails , the transmission is on borrowed time . There are like 9 or 10 in a kit , spread through out the transmission . Another is the end shaft play adjustment . This is made by various thickness plastic disks . You start with what thickness came out of the transmission , Assemble Transmission to point you can check end play and hope it is right . Otherwise , pull apart and go thicker or thinner . The problem is the disk itself .

We looked at the $5000+ custom rebuilt's , All had the same thrust washers and thrust bearings . I am not knocking any one who is into that kind of power , what ever floats their boat . I use to love going to the diesel bulletin boards and reading the stories and their questions on " Why " it happened . I am a practical type , If it works as is , Don't mess with it .

Fred H.

Raspy · Jan 21, 2019

One thing I finally figured out is that Chrysler only builds the trannies strong enough to handle stock power. They have a number of very strong factory parts for the 48re, for instance, but didn't use them in production trucks because the tranny could be made strong enough with cheaper parts. I don't blame them. They are not obligated to build a trans strong enough for sled pulling just to carry stock power. And anything can be broken if someone tries hard enough. Speaking of thrust bearings, that is what finally made the 48re approved for engine brakes. Apparently, thy went from a brass thrust to a roller bearing thrust to take the reverse push while the brake was on. They also have a killer second gear band that is way stronger than stock. But like the weak clutches they put in front of the G56, the lockup clutch in the 48re is barely strong enough. I toasted mine.

The Aisin is a completely different animal. It easily weighs three times as much as the 48 and the torque converter is the tightest I've ever experienced. It's rated to hold somewhere around 1,200 ft lbs in stock form. You definitely don't want to rev it up above about 1000 RPM and put it in gear, and it will pull away under heavy load at a high idle with very little slipping. Then the lockup strategy includes a lock with every shift in a very seamless manner. The tranny runs cooler than the engine oil and as long as it stays locked it will not create noticeable heat. So, full throttle pulls in the mountains are just normal for it. Every fluid change, the oil comes out bright red with no metal. The possible downside it is has no internal governor and is completely computer controlled. Further, the computer is locked and the code hasn't been broken to get in. So the stock map is all you get. That means if you tune the engine it becomes out of synch with the engine. Shifting may be at the wrong time and it shifts too softly.

Going to 4.10 gears helps and is the gear they should come with in my opinion. Mine went from lugging and annoying and slow to respond, to quicker and better to drive. Towing improved significantly.

bdog · Jan 22, 2019

I still haven’t found a clear answer. Is the 1k torque only available in the 3500 or can you get it on the 2500?

I am ditching my F-450 and doing all my hauling with the semi. I bought a 43’ lowboy trailer a few weeks ago and it is about as easy to take anywhere as my 450 and 32’ GN.

My plans are to just have a 3/4 ton to drive around and no longer have a dually or do any serious towing with a pickup.

Monster5601 · Jan 22, 2019

bdog said:
I still haven’t found a clear answer. Is the 1k torque only available in the 3500 or can you get it on the 2500?

I am ditching my F-450 and doing all my hauling with the semi. I bought a 43’ lowboy trailer a few weeks ago and it is about as easy to take anywhere as my 450 and 32’ GN.

The 1K torque output is only available with the Aisin transmission and only on the 3500 SRW or dually.