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Old 05-14-2013, 05:45 PM   #1
Dale99
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np205 shifter jump?

So I noticed when my np205 is in 4low, fronts locked in, and I make a turn the shifter jumps. It did this so much that it kicked the front out of 4low, but left the rear in 4low. This is still with the stock setup, not a twin stick.

Is this normal, or something wrong?
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Old 05-14-2013, 06:42 PM   #2
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Re: np205 shifter jump?

Check your transfercase mounts. If its bouncing that much also verify the ratios match.
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Old 05-14-2013, 09:54 PM   #3
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Re: np205 shifter jump?

which mounts as I just put it in there?

4hi does not do this, and 4low strait line does not do this. If gears where miss-matched, wouldnt it show then as well?
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Old 05-14-2013, 09:58 PM   #4
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Re: np205 shifter jump?

Check for cracks in your adapter too.
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Old 05-14-2013, 09:59 PM   #5
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Re: np205 shifter jump?

When turning there is a certain amount of driveline wrap up due to tires on all 4 corners going different speeds. Thos would cause stress on all the mounts and if there is a bad one move the shifter against the body in the shifter hole and disengauge the front. However if your transfercase is giving you 2wd low there is a internal problem with your transfercase. Lets inspect both motor mounts and all transfercase mounts to first rule that out.
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Old 05-14-2013, 10:18 PM   #6
Dale99
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Re: np205 shifter jump?

All new mounts and adapters.


btw, I'm talking forwards/backwards movement. Not left to right.
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Old 05-14-2013, 10:27 PM   #7
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Re: np205 shifter jump?

Are you doing this on pavement ?
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Old 05-14-2013, 10:29 PM   #8
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Re: np205 shifter jump?

Shift collars have teeth that are worn out. Been jammed into gear alot and rounded the teeth off of the collar or the shaft side of it. They are now "ramped" so to say.

That is one potential issue.
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Old 05-15-2013, 06:44 AM   #9
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Re: np205 shifter jump?

custom10, no dirt in my friends back yard
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Old 05-15-2013, 08:06 AM   #10
burnin oil
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Re: np205 shifter jump?

Sounds internal. If you engauge 4x4 and just drive straight does it stay in gear? If it is still jumping out the poppet ball/springs on the shifter rail could be worn also. Had this issue on a NP205 years ago. Lock it in gear and a second or two later it would jump back out. Almost like a bad syncro/dog assembly in a transmission.
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Old 05-15-2013, 10:06 AM   #11
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Re: np205 shifter jump?

Going strait it seemed to stay. The ball/poppet your talking about is under the plugs on the top of the tc correct?

The top rod is also front driveshaft correct?
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Old 05-15-2013, 10:11 AM   #12
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Re: np205 shifter jump?

Top rail is rear. Lower is front. The rails shift the output theyre closest to.
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Old 05-15-2013, 11:11 AM   #13
burnin oil
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Re: np205 shifter jump?

Quote:
Originally Posted by Dale99 View Post
Going strait it seemed to stay. The ball/poppet your talking about is under the plugs on the top of the tc correct?

The top rod is also front driveshaft correct?
Sure are. They function as a locking mechanism to hold the shift rails in the correct location on the detents. When the spring looses tension the rails become free to bounce around and jump out of gear.
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Old 05-15-2013, 12:10 PM   #14
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Re: np205 shifter jump?

thanks obijuan

burnin oil. Then I would guess the springs are worn/collapsed. Or atleast thats part of the problem then.
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Old 05-15-2013, 01:31 PM   #15
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Re: np205 shifter jump?

Or the rail itself has a groove worn in it from the detent ball.
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Old 05-15-2013, 02:43 PM   #16
Dale99
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Re: np205 shifter jump?

Would I beable to see that when its pulled in the outmost position(4hi?)?
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Old 05-15-2013, 02:55 PM   #17
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Re: np205 shifter jump?

To see the wear? No that stays in the case.
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Old 05-16-2013, 09:23 AM   #18
burnin oil
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Re: np205 shifter jump?

I think the rail could have all kinds of wear and still function fine as long as the seal surface is good. the poppet springs are really nothing more than an over sized bic pen spring. Like said before this may not be the problem and it could be internal.
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