M1008 service truck- transmission issues

[Druff]

Some of you mightve seen i recently bought a contractor operated CUCV thats got a utility bed.

Recently got her all squared away to hit the road and the tranny wont shift until redline.

What do i need to check?

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[NDT]

Everything associated with the vacuum modulator: The vacuum pump, the hoses, the transmission vacuum regulator valve on the injection pump, or the modulator on the transmission. If all this works perfect, check for stripped plastic governor gear.

 

[Druff]

Everything associated with the vacuum modulator: The vacuum pump, the hoses, the transmission vacuum regulator valve on the injection pump, or the modulator on the transmission. If all this works perfect, check for stripped plastic governor gear.

Was the vacuum pump. Its barely generating 5inhg of vacuum.

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[Prepper_Pig]

My m1009 also started this after a couple of rough starts during the artic blast we had a couple weeks ago. I've yet to identify the problem though.

 

[Druff]

So an update, i THOUGHT it was the vacuum pump. Everything in the vacuum system is working correctly now. Even took a vacuum modulator off a working th400 to rule out new but bad parts. Still wont shift till the redline. Starting to think i need to tear into the transmission as it seems the rod that controls the line pressure is stuck at max.

Course its really not hurting anything to keep the max line pressure, other than spinning the 6.2 up to 4k rpm. But its a detroit they like it

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