Allison 5sp: P0700,p0734,p0776,p0843

[03 D-max]

So here is the deal, when shifting from 3rd to 4th the truck reds as though you put it in nuetral and then limps. If you let off the throttle when it shifts it will take a second and go in fine. 4th gear works fine unless you try to lock the converter and then it will rev as though you put it in neutral. So basically it won't 3-4 shift without letting off and you can't lock converter in 4th, all other gears and shifts work great. I have changed spin on.

Codes 0700,P0734,P0776,P0843
Truck in sig 216,000mi stock transmission

Please help :dontknow:

 

[onebaddmaxxx]

The p0776 code and having issues engaging 4th might indicate a striped p2 planet or c2 hub.

Who's tuning?

 

[03 D-max]

Idaho robs

 

[Mike L.]

If the splines were stripped, there would be no 4th.

 

[03 D-max]

That is what I assumed and 4th does work as long as the converter does not lock, I am assuming it is maybe a pressure problem but I am not really sure. I would like to be able to get it fixed with out spending 5k on a built transmission, the truck is just a work truck now with a little tow tune

 

[Mike L.]

Trans is coming out for sure. C2 and C3 will be toast. C2 hub splines will be twisted but to what extent we don't know. It's not a pressure problem. It's a right foot problem.

 

[c20elephant]

I have a 5 speed in the bed of my truck right now, let me know what parts you need....

 

[03 D-max]

Right foot problem.... impossible lol :driving:
Honestly I am glad it has made it to 216,000
I have been driving it this way for the past 18months, just wind it up in 3rd let off until it grabs 5th and good to go, drop below 35 and shift back to 3rd. Is there anything more to be ruined if I just keep driving it? At this point I am assuming it will be ok for a core either way? It's a rusty NY work truck that gets about 5000mi a year tops

 

[03 D-max]

BTW thanks for the quick responses :hug:
Life has been so busy it has been 3yrs since I last logged in. I was getting sick of driving it this way and knew Mike L would be able to give me some sort of idea. Still seems to be one of the best forums for help out there!