Transfer case wont stay in gear

[blowinsmoke97]

upon returing home from Florida to NC while towing a sazuki sammy, my truck popped itself into neutral at the t-case. it did this again after puting it back into 2wd, and i noticed it did it every time i lifted my foot off the pedal. it finally got to the point were i had to hold it in 2wd and pull back on the t-case shift lever just to keep it moving. now it wont move and the gears grind. it seems almost as if the shift lever is being pulled on whemever i get off the gas, and thats why its poping out. put it in 4wd today and moved it a little, it poped into 2wd this time, then from 2wd it did as already described. linkage is good, not abnormal play in it. anyone have this problem, if so how do i go bout fixing this. i hate making payments on somehing sittin in my yard doing me no good!

[grancito]

What year is your truck? I have the 2 below, and had problems twice with 82. It stripped the drive in the trans case twice. It is a crap design, both vehicles have the same trans case, the first time I built the stripped teeth up with weld, the second time I cut the pieces, 4 parts, out one at a time and welded in a piece of 1/4 inch plate which I'd grinder cut teeth in. Cutting every tooth instead of the original one tooth space between each. This part would be expensive as it is large and also houses the planetary gears for low ratio. It is not difficult to to work on. You could find that the bearings are worn, and this would make it become disengaged.

[blowinsmoke97]

the truck is a 97 , whats the best way to go about checking that?

[grancito]

I added a bit saying that the bearings could be worn. Drop the drive shaft, drain the trans case, unbolt the rear oval cover, undo the nut on the top shaft and slide the chain and sprocket back, then the chain will come off. Disconnect the 4WD linkage and pull on the shaft and the whole lot will come out. Watch where the roller thrust bearings fall from, there is one right up the front. I don't think the system has changed from 94 to 97 as it looks the same in 82 and 94, also same in 95 Dodge.

[MBBOB]

I personally would not do all that under the truck. Once the shaft and linkage are off, only a few more bolts to get the case off and onto a bench.
I had the same problem with a 241 case and it turned out the shift fork for the 2-4 wd has small plastic wear pads that wore out, coupled with a slight bend in the fork from yanking once too hard. The combination let the slider coupling walk out far enough to disengage when you let off the gas. If you need a new fork get an OEM as they are weak to begin with and the first aftermarket one I bought was real junk.

[blowinsmoke97]

yeah thats what my buddies up at Chevy told me, the plastic wears out, how big of a pain is it to replace that fork?

[MBBOB]

Once the case is on the bench and opened up it is easy, but once the guts are out I would suggest replacing the chain at least, if you have some miles on it. When you replace the fork stick the plastic pads on with some silicone early to keep them from falling off until you get the fork in place.

Once again, check on the fork with GM because I think there was a revised fork that is stronger.

Also check the teeth on the end of the sliding collar that the fork actuates and the female gear it slides into to see if they are rounded off or chewed up from jumping in and out. They are bigger dollar parts you may not want to replace, but you also do not want to do the job twice.

[sootjunkie65]

My trucks doing the same thing and im not gonna fool around rebuilding it because I found a site online that will send me a fully rebuilt NP241 C for 670 bucks. Plus its a direct factory fit, just a few bolts on the tranny and the driveshafts to pull out and it bolts back in, piece of cake its way easier than fooling around with a rebuild plus once you factor in parts and labor its not much more than rebilding it yourself.