Good replacement for an Allison MT-41

[DannyB1954]

This transmission went out of production back around 1972, but I do have one in a 1974 class A motor home. It was put in years after the coach was built, so it may not be set up correctly for the loads now carried.

The problem that I have is that the transmission is a 6 speed, but unless manually selected it always starts off in 3rd gear, (normal for this model). Where the problem comes in is when the transmission shifts from 5th to 6th. It does so at about 2,300 RPM. In sixth gear the RPMs drop to about 1,700 RPM.

My engine, (DD6V53), develops it's max HP at 2,800 RPM. At 1,700 RPM it has very little power. On flat land this is not a problem, but going uphill the engine bogs down and smokes a lot. The question is, can the shift point be increased to say 2,700 rpm, so that in the next gear the engine will have higher RPM's and power?

Failing an adjustment, what would be a good economical replacement, (used take out)? The coach is old, and I do not want to drop a ton of money into it.
Any advice or input?

[GOLDWINGER2]

Just hold 5th manually until the hill climb is over.
J

[DannyB1954]

I found the solution. I purchased a service manual from EBAY. There is a cable that runs from the throttle on the engine to the tranny. The more travel this cable has, the more it rotates the lever on the tranny . This causes it to shift later, (at a higher RPM).

I originally thought it was a passing gear kick down lever. when I tried to adjust it by just shortening the cable, it would not shift into high gear at all. When I adjusted the cable so that it would go into high gear, it shifted too early, (low RPM's).

I lengthened the arm on the throttle so that it would move the cable a further distance and this appears to do the job. At low throttle positions the arm on the tranny is not rotated enough to cause no shift to high gear, but at full throttle it is rotated enough to shift later, (at higher RPM's). What a difference in performance.

[YosemiteBobR]

It's so great when people return to give their solution, Thank you

[FleetMan]

I say this in jest but it is a great example of that old phrase, "When all else fails, Read the instructions!"