NP242 Full Time not working, Front axle not engaging
11-04-2012, 11:21 PM
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NP242 Full Time not working, Front axle not engaging
Ok so heres a long question!
Short story:
4WD is not working properly, the rear differential is working but not the front. (I put the front wheels on a rail road tie while the rear were on soft dirt and the rears spun in 4WD low and I did not climb the tie). And yes I have the NP242 transfer case, but I had to switch the front to a CAD type Dana 30, but I have the Posi Lok 4X4 in it and it is engaged. The strange thing is, when the t-case is in Full time, there is a strange grinding and the vehicle doesn't move...
Long story:
Ok so the long story goes along with the short one, but adds a bit. So, the vehicle was in an accident, passenger side got hit hard on the wheel and bent the axle. That was the reason for the CAD switch, also, the CAD was 4.11's so I jumped on it and got a 35 with the 30 as well. Anyways, now that that was all done, the lift and 33's went on with the posi lok. We wheeled with it once and the axle was engaging. So heres how it goes: 2WD high : Rear drive shaft spins and vehicle drives, 4WD High Part Time : Front and Rear Drive shaft spin and vehicle moves, 4WD High Full Time : Only Front Drive shaft spins and vehicle doesn't move and there is a kind of a grinding noise, 4WD Low Part Time : Both drive shafts spin, vehicle moves, but front is not engaging at all. Now I also noticed that when the posi lok is engaged, the passenger wheel will spin without the drive shaft or other wheel moving, but when the driver side wheel is spun, the drive shaft turns, but not the passenger tire. So, what could it be, need a new t-case? Or a new axle parts, or both? If it is axle parts please be specific. This is a DD and I need to fix it quick. Oh, and when I looked in the disconnect cover, I found a couple of metal parts, needle bearings and a little of what I am assuming was the end of the bearing they came out of, so I know that I need to replace a bearing in there but I don't think this could be causing the problem. I can also post a video if anyone wants it sense its kinda confusing to type up. Thanks in advanced Ben and Kay!
Short story:
4WD is not working properly, the rear differential is working but not the front. (I put the front wheels on a rail road tie while the rear were on soft dirt and the rears spun in 4WD low and I did not climb the tie). And yes I have the NP242 transfer case, but I had to switch the front to a CAD type Dana 30, but I have the Posi Lok 4X4 in it and it is engaged. The strange thing is, when the t-case is in Full time, there is a strange grinding and the vehicle doesn't move...
Long story:
Ok so the long story goes along with the short one, but adds a bit. So, the vehicle was in an accident, passenger side got hit hard on the wheel and bent the axle. That was the reason for the CAD switch, also, the CAD was 4.11's so I jumped on it and got a 35 with the 30 as well. Anyways, now that that was all done, the lift and 33's went on with the posi lok. We wheeled with it once and the axle was engaging. So heres how it goes: 2WD high : Rear drive shaft spins and vehicle drives, 4WD High Part Time : Front and Rear Drive shaft spin and vehicle moves, 4WD High Full Time : Only Front Drive shaft spins and vehicle doesn't move and there is a kind of a grinding noise, 4WD Low Part Time : Both drive shafts spin, vehicle moves, but front is not engaging at all. Now I also noticed that when the posi lok is engaged, the passenger wheel will spin without the drive shaft or other wheel moving, but when the driver side wheel is spun, the drive shaft turns, but not the passenger tire. So, what could it be, need a new t-case? Or a new axle parts, or both? If it is axle parts please be specific. This is a DD and I need to fix it quick. Oh, and when I looked in the disconnect cover, I found a couple of metal parts, needle bearings and a little of what I am assuming was the end of the bearing they came out of, so I know that I need to replace a bearing in there but I don't think this could be causing the problem. I can also post a video if anyone wants it sense its kinda confusing to type up. Thanks in advanced Ben and Kay!
11-04-2012, 11:38 PM
#2
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Sure sounds to me like you have a gear problem, especially since you found some metal in the disco housing. You sure both axles had 4.11 gears? You may have thrashed your pinion or tcase if the gears were different and you played around in 4wd.
Pull the diff cover and have a look at your ring and pinon gears. If both driveshafts are moving but the vehicle wont at all, then both front and rear axle have gear issues because if the ds moves, the vehicle should.
The 242 full time is designed so that when it senses wheel slippage it puts the vehicle into 4wd and sends power to that wheel. If you try to use full time when the posi is not engaged, im guessing its messing some kind of synchro up.
You have an interesting situation here, not often u see a cad axle with a 242 tcase. You sure the posi is working right and locking the collar onto the two shafts when u engage it?
Either way, the front wheels will not have power, ever, if the front ds is not turning. If it is turning and you have no 4wd, look at your ring and pinon. Or your posi isnt working and because you have an open diff and not a locked diff, all the power is being sent to the disco'd side. IMO pop open the diff cover and have a look, if all looks well, make a block off plate, get rid of the posi and cad housing, and put a llong shaft from your old axle in it. Then if the tcase still has problems, you know its the tcase.
Pull the diff cover and have a look at your ring and pinon gears. If both driveshafts are moving but the vehicle wont at all, then both front and rear axle have gear issues because if the ds moves, the vehicle should.
The 242 full time is designed so that when it senses wheel slippage it puts the vehicle into 4wd and sends power to that wheel. If you try to use full time when the posi is not engaged, im guessing its messing some kind of synchro up.
You have an interesting situation here, not often u see a cad axle with a 242 tcase. You sure the posi is working right and locking the collar onto the two shafts when u engage it?
Either way, the front wheels will not have power, ever, if the front ds is not turning. If it is turning and you have no 4wd, look at your ring and pinon. Or your posi isnt working and because you have an open diff and not a locked diff, all the power is being sent to the disco'd side. IMO pop open the diff cover and have a look, if all looks well, make a block off plate, get rid of the posi and cad housing, and put a llong shaft from your old axle in it. Then if the tcase still has problems, you know its the tcase.
Last edited by OleBlue; 11-04-2012 at 11:47 PM.
11-05-2012, 05:56 AM
#3
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Actually, the 242 is designed with a regular old differential in it that when in Fulltime will send all the power to the driveshaft that is slipping. Parttime locks the differential in the transfer case so it works like a 231.
Sounds like you have two problems. Here's a scenario. The cAD hasn't been engaging properly even though you have the posi-lock. That's why your right front wheel turns freely. The thing could be misadjusted or have a bent fork. If it were me, I would just lock the front axle in using one of the good wrie-ups on CF, after verifying the situation in the front diff.
Now, if you ran the 242 in Fulltime with a wonky connection in your CAD, it has been sending all the power to a spinning diff in the front at different times. That has most likely trashed some components in the transfer case.
Sounds like you have two problems. Here's a scenario. The cAD hasn't been engaging properly even though you have the posi-lock. That's why your right front wheel turns freely. The thing could be misadjusted or have a bent fork. If it were me, I would just lock the front axle in using one of the good wrie-ups on CF, after verifying the situation in the front diff.
Now, if you ran the 242 in Fulltime with a wonky connection in your CAD, it has been sending all the power to a spinning diff in the front at different times. That has most likely trashed some components in the transfer case.
11-05-2012, 11:34 AM
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Sure sounds to me like you have a gear problem, especially since you found some metal in the disco housing. You sure both axles had 4.11 gears? You may have thrashed your pinion or tcase if the gears were different and you played around in 4wd.
Pull the diff cover and have a look at your ring and pinon gears. If both driveshafts are moving but the vehicle wont at all, then both front and rear axle have gear issues because if the ds moves, the vehicle should.
The 242 full time is designed so that when it senses wheel slippage it puts the vehicle into 4wd and sends power to that wheel. If you try to use full time when the posi is not engaged, im guessing its messing some kind of synchro up.
You have an interesting situation here, not often u see a cad axle with a 242 tcase. You sure the posi is working right and locking the collar onto the two shafts when u engage it?
Either way, the front wheels will not have power, ever, if the front ds is not turning. If it is turning and you have no 4wd, look at your ring and pinon. Or your posi isnt working and because you have an open diff and not a locked diff, all the power is being sent to the disco'd side. IMO pop open the diff cover and have a look, if all looks well, make a block off plate, get rid of the posi and cad housing, and put a llong shaft from your old axle in it. Then if the tcase still has problems, you know its the tcase.
Pull the diff cover and have a look at your ring and pinon gears. If both driveshafts are moving but the vehicle wont at all, then both front and rear axle have gear issues because if the ds moves, the vehicle should.
The 242 full time is designed so that when it senses wheel slippage it puts the vehicle into 4wd and sends power to that wheel. If you try to use full time when the posi is not engaged, im guessing its messing some kind of synchro up.
You have an interesting situation here, not often u see a cad axle with a 242 tcase. You sure the posi is working right and locking the collar onto the two shafts when u engage it?
Either way, the front wheels will not have power, ever, if the front ds is not turning. If it is turning and you have no 4wd, look at your ring and pinon. Or your posi isnt working and because you have an open diff and not a locked diff, all the power is being sent to the disco'd side. IMO pop open the diff cover and have a look, if all looks well, make a block off plate, get rid of the posi and cad housing, and put a llong shaft from your old axle in it. Then if the tcase still has problems, you know its the tcase.
Actually, the 242 is designed with a regular old differential in it that when in Fulltime will send all the power to the driveshaft that is slipping. Parttime locks the differential in the transfer case so it works like a 231.
Sounds like you have two problems. Here's a scenario. The cAD hasn't been engaging properly even though you have the posi-lock. That's why your right front wheel turns freely. The thing could be misadjusted or have a bent fork. If it were me, I would just lock the front axle in using one of the good wrie-ups on CF, after verifying the situation in the front diff.
Now, if you ran the 242 in Fulltime with a wonky connection in your CAD, it has been sending all the power to a spinning diff in the front at different times. That has most likely trashed some components in the transfer case.
Sounds like you have two problems. Here's a scenario. The cAD hasn't been engaging properly even though you have the posi-lock. That's why your right front wheel turns freely. The thing could be misadjusted or have a bent fork. If it were me, I would just lock the front axle in using one of the good wrie-ups on CF, after verifying the situation in the front diff.
Now, if you ran the 242 in Fulltime with a wonky connection in your CAD, it has been sending all the power to a spinning diff in the front at different times. That has most likely trashed some components in the transfer case.
Thanks again for the reply's guys, this is a DD and I do all of the work myself so I really appreciate it.
11-05-2012, 11:53 AM
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the collar needs to be half on each shaft, thats what connects the two shafts to give power to that wheel. Like i said, get rid of that cad crap and just stuff a longside shaft in there.
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