I'm working on a modified xm211. It's had a chevy engine/4 speed manual trans installed. The truck drivetrain seems to "bind up" when in reverse and turning (much the same feel as a "full time 4wd" truck). I think I've read something about a sprag(s) in the transfer case that were "shifted" via the auto trans shifter. If so, I need to understand how this worked so I can "fix" it. I imagine this info is at my fingertips on this site, but I can't seem to find it. Could someone point me in the right direction please?
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xm211 transfer case question
- Thread starter Ashley P
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Section8
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I am not entirely sure if I am correct with this but this how my transfer case was explained to me.
When you are under your truck and are looking at the front side (facing the engine tranny) on the top left of the case is a small cylinder type plunger actuator(sprag).
This is typically linked with arms to the shifter arm off the tower in the stock automatic engine tranny.
Since you have a Chevy with 4 speed manual tranny in place instead of the stock set up you need to ensure you have a linkage to this (sprag) actuator on the top left of the forward face on your transfer case.
This (sprag) is dual actuating. It needs to be forward or pull out to operate the transfer case for normal forward motion, either 4x4 or 2 wheel drive, and pushed in rearwards for the transfer case to run in reverse.
I will try to post a picture of my transfer case to show.
When you are under your truck and are looking at the front side (facing the engine tranny) on the top left of the case is a small cylinder type plunger actuator(sprag).
This is typically linked with arms to the shifter arm off the tower in the stock automatic engine tranny.
Since you have a Chevy with 4 speed manual tranny in place instead of the stock set up you need to ensure you have a linkage to this (sprag) actuator on the top left of the forward face on your transfer case.
This (sprag) is dual actuating. It needs to be forward or pull out to operate the transfer case for normal forward motion, either 4x4 or 2 wheel drive, and pushed in rearwards for the transfer case to run in reverse.
I will try to post a picture of my transfer case to show.
Thank you Section 8, but don't go to any more trouble for me just yet. I've stumbled into data that appears to be what I need to know. In the Tech Man download 2 of 6, on pages 84, 88, & 94. Page 88 seems to say to move the shift shaft in the opposite direction that you mentioned. ??? Either way, I know what shaft to move, and that's MILES more than I knew before. Obviously I'm a beginner to this truck, so please forgive my ignorance.
Section8
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Ok. Been a while since I actually looked at my transfer case.
It isn't a small actuator it's the main actuator and more in the middle of the case just above the front drive shaft out put.
This needs to either pulled out to go forward or pushed into the case for reverse. It also has to stay in to keep the actuator from popping out.
This is spring loaded so it will pop out if not held in place. This is to ensure a neutral position so as to not have the transfer case in the wrong engagement for the wrong direction of travel.
It isn't a small actuator it's the main actuator and more in the middle of the case just above the front drive shaft out put.
This needs to either pulled out to go forward or pushed into the case for reverse. It also has to stay in to keep the actuator from popping out.
This is spring loaded so it will pop out if not held in place. This is to ensure a neutral position so as to not have the transfer case in the wrong engagement for the wrong direction of travel.
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Section8
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I am probably bass ackwards with my linkage throws.
You can't beat the TMs so in is forward and out is reverse.
Keep us posted and we will all help as we can.
I would be interested to see pics of your engine swap and corresponding linkages and such.
So I will say it before someone else.
Post pics!
You can't beat the TMs so in is forward and out is reverse.
Keep us posted and we will all help as we can.
I would be interested to see pics of your engine swap and corresponding linkages and such.
So I will say it before someone else.
Post pics!
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Never seen a jimmy case with a spring on the front drive selector. Interesting.
The jimmy does NOT have a sprag front propeller shaft drive. It has a dog clutch, same concept, just more forgiving.
I also do not recall there being a neutral position, always forward or reverse. They were actuated (shifted) by a linkage rod from the transmission tower.
The TM's should give you the info.
The jimmy does NOT have a sprag front propeller shaft drive. It has a dog clutch, same concept, just more forgiving.
I also do not recall there being a neutral position, always forward or reverse. They were actuated (shifted) by a linkage rod from the transmission tower.
The TM's should give you the info.
Section8
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I am basing my information of what I have experienced when I took my engine and tranny out.
My transfer case may be botched I don't know.
I do know that when I took the engine and tranny out and disconnected the linkages to the transfer case there was a pop and the linkages and such set in a middle or (play) area. I could then free spin my transfer case by hand. If I pushed or pulled the actuator wither way it would engage and I could not spin it due to rear drive propeller still being attached.
As always refer to the TM.
My transfer case may be botched I don't know.
I do know that when I took the engine and tranny out and disconnected the linkages to the transfer case there was a pop and the linkages and such set in a middle or (play) area. I could then free spin my transfer case by hand. If I pushed or pulled the actuator wither way it would engage and I could not spin it due to rear drive propeller still being attached.
As always refer to the TM.
I also saw this post with relevant info: http://www.steelsoldiers.com/showth...ips-for-the-GMC-transfer-case&highlight=sprag Maybe in the next few days I'll get to experiment with the shift shaft.
Section 8: Photos? I'm pretty shy about photos (plus the truck is not very photogenic
). And I bought the truck already modded. Other than the sbc/4 speed, it's got a hydraulic pump and twin cylinder hoist under the bed, so now it dumps. Also has a vacuum booster on the brakes. Seems someone stripped a late 60s GM "2 ton" farm truck (c50/c60) for all those parts.
Section 8: Photos? I'm pretty shy about photos (plus the truck is not very photogenic
). And I bought the truck already modded. Other than the sbc/4 speed, it's got a hydraulic pump and twin cylinder hoist under the bed, so now it dumps. Also has a vacuum booster on the brakes. Seems someone stripped a late 60s GM "2 ton" farm truck (c50/c60) for all those parts.
USMC 00-08
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Good job on digging into those TM's! Welcome to the forum! No ignorance on your part. I think it is safe to say that we are all learning things about these trucks.
I'd like to see some pictures of your truck and the engine/transmission combo when you have a chance.
I see my truck appears to have a handle connected to the linkage, when I get some more fuel I'll try it out.
Found a relative post: http://www.steelsoldiers.com/showth...ips-for-the-GMC-transfer-case&highlight=sprag
Folks, as for photos, my stuff is all camera shy.
The engine/trans install is not pretty, but seems functional. Also it's got the brake booster/secondary master cylinder from a GM "2 ton" (c50/c60) farm truck, and a hydraulic pump/twin piston bed hoist, so it dumps now. It needs brake, radiator, lighting, heating, wiper, winch attentions. But this truck is a back, back, back burner (sometimes I find it behind the stove) kinda project, so I've accomplished a relative TON in this discussion/investigation.
So thanks forks for the info/help.
Found a relative post: http://www.steelsoldiers.com/showth...ips-for-the-GMC-transfer-case&highlight=sprag
Folks, as for photos, my stuff is all camera shy.
The engine/trans install is not pretty, but seems functional. Also it's got the brake booster/secondary master cylinder from a GM "2 ton" (c50/c60) farm truck, and a hydraulic pump/twin piston bed hoist, so it dumps now. It needs brake, radiator, lighting, heating, wiper, winch attentions. But this truck is a back, back, back burner (sometimes I find it behind the stove) kinda project, so I've accomplished a relative TON in this discussion/investigation.So thanks forks for the info/help.
tburk49760
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My truck has a Detroit diesel and 5spd trans swapped in. There was a strange spring operated switch mounted to the shift lever when I got it that a powered an air cylinder. The air cylinder would move the transfer case shift rod in the appropriate direction when the trans was shifted into reverse. I didn't like the flakiness so installed a push pull switch. I just need to remember to pull the switch when I back up. If only there were a reverse light switch on my transmission...
Wow, it's almost 3 months since I started this topic. A couple months ago I found that what appeared to be the correct shift shaft had some linkage to a lever in the cab. I studied it and experimented with shifting it while turning sharp and moving forward and backward. The driveline still seemed to bind no matter what way I "shifted" it. Obviously, this truck is a back-back burner project. And I think I've exhausted all the time on it that I want to this year. And maybe next... lol
Sorry USMC 00-08, I don't do the pic thing very much. A short time after you asked I attempted a reply (that the computer ate) and I walked away till now. The truck has faded ODish paint, a cracked driver windshield, no wipers, and a winch that needs a cable replaced. The bed dumps thanks to what appears to be a hoist from a "2-ton" grain truck (probably where the engine/trans came from, too). Also from a grain truck is a vacuum booster. This fall I managed to put a different master cylinder on, bleed the brakes, and replace both PTO cables. I temporarily had brakes, until a wheel cylinder bled them dry for me. As I mentioned, I'm outta gumption for now.
Sorry USMC 00-08, I don't do the pic thing very much. A short time after you asked I attempted a reply (that the computer ate) and I walked away till now. The truck has faded ODish paint, a cracked driver windshield, no wipers, and a winch that needs a cable replaced. The bed dumps thanks to what appears to be a hoist from a "2-ton" grain truck (probably where the engine/trans came from, too). Also from a grain truck is a vacuum booster. This fall I managed to put a different master cylinder on, bleed the brakes, and replace both PTO cables. I temporarily had brakes, until a wheel cylinder bled them dry for me. As I mentioned, I'm outta gumption for now.
Back to this question of transfer case "shifting" for forward or reverse. I've been messing with the rear brakes and have all 4 rear axles out. The truck will drive forward but will no back up. I suppose now is the time to figure out that linkage...
....and, as a solution to my question: the truck had been modified with a lever to actuate the push/pull "rod" on the front top/right side of the transfer case. It works well now that I understand it.
....and, as a solution to my question: the truck had been modified with a lever to actuate the push/pull "rod" on the front top/right side of the transfer case. It works well now that I understand it.
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