NP 241 Rebuild needed?

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Daveo91Burb

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My NP 241 will fall out of 4-Hi. I’ll be driving along in 4wd in snow and all of a sudden I’ll lose traction and realize it’s back in 2 hi. I think there are some plastic bushings on the shift forks that may be the culprit? Does this mean full rebuild? I have the t-case out now so it’s probably a good time. Everything else is OK except input and output seals. I was just going to do those and call it good, but now I’m thinking I should crack the case and at a minimum replace anything plastic or rubber.

If there is agreement I should crack it open, any good advice on rebuild kits? I’m thinking the chain should not need replacement?
 

HotRodPC

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I wonder if @crazy4offroad or @bucket might have a clue for certain. I'm sure not certain with that one. I've only dealt with ones that work and then explode or replacing seals and bearings, not diagnostics as of yet to much.
 

bucket

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I don't know much about the guts. But I know a linkage that's out of adjustment can cause that issue, as well as a bad trans mount.
 

Daveo91Burb

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Hmmm, the trans mount IS bad, there’s a crack in it and new one on order. Maybe that’s the problem? It sure would be nice to not have to crack that thing open! Thanks for the input


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bucket

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The shifter mounts to the body, so if the body moved too much in relation to the t-case, it can cause it to shift. But some movement is normal too, so if the linkage is out of adjustment, it can cause the same issue.
 

Daveo91Burb

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Cool. Well I’ll replace the trans mount and adjust the linkage and keep my fingers crossed! thanks
 

Daveo91Burb

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Just closing the loop on this one, finally got it resolved: simple case of linkage needing adjustment. I took the shifter console plate off so I could observe how it operated in the gate and saw that in 4-Hi the shift lever was bumping against the metal gate before it could go all the way into the detent. Super easy to remove the linkage and move the pinning point further down the linkage rod. Works like a charm now.

Actually needed 4wd a few times this last week due to some minor snow on the roads. It kind of sucked to have to hold the t-case lever while driving.
 

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I remember back on the np203 and it seems like on the np205 I thought the shifter was attached to the transfer case. I wonder why GM decided to go away from that? Was it a change after the body style updates?
 

bucket

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I remember back on the np203 and it seems like on the np205 I thought the shifter was attached to the transfer case. I wonder why GM decided to go away from that? Was it a change after the body style updates?

It was more modern and sophisticated. The shifter didn't move or shake as you drove the truck.
 

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