[l.jpeterson]

Just put a np205 behind my 700-r4 chopped a small bit of the tailshaft off and got the adapter plate from advanced adapters. Everything seems to work fantastic foot on the gas, however during deceleration it sounds like there is excessive backlash in the gears and it makes a grinding/ spooling sound. My father has the same set up in his jeep and it does not make these sounds, just wondering if someone could give me some help as to whats going on. I am running atf in the tcase not sure if I should change it to gear oil being behind an auto tranny. Some help please

 

[ToughBowtieTruck]

205s are supposed to be gear oil . . .

 

[Cheepin]

205s are supposed to be gear oil . . .

This

 

[SMC]

Its not like a borgwarner unit that shares its fluid with the trans. Its self contained and gear driven. Unlike a BW which uses a chain and a sungear system. Get some good full synthetic gear oil in there and it will solve all your problems.

 

[sjracer]

thrust washer missing somewhere? possibly in the center idler gear set.

 

[l.jpeterson]

So I tried switching fluid out still same problem, I guess thrust washer could be a possibility. Although it appears it has never been apart before. All the outer seal and etc I replace they were the original o.e seals

 

[TheMountain]

What did you change the tcase fluid to? Should be 80/90W oil.

 

[T-A-I]

No idea where you are located, but more than likely too far from me to be worthwhile. If you end up needing another NP205, I have a good working one that I'll more than likely never use that needs a good home...

 

[l.jpeterson]

Yup thats what I used is 80W....im in Washington

 

[KWTMECH]

Does the adapter retain the front input bearing against the t-case, or does it require a separate alum piece for the seal?

did you take the assembly apart or just replace the seals?

 

[77k5]

ATF or gear oil is fine, they were both factory spec.

Your problem is a driveline vibration, gear driven transfer cases commonly make noise because of it.

You didn't say what vehicle, but if you can, pull the rear driveshaft. Then put it in 4WD and try driving it on the highway in front wheel drive. A lot of times the front shaft will vibrate less (because it's usually a CV) and make the t-case a lot quieter, and then you know what the issue is.

 

[l.jpeterson]

It did retain the front input bearing nothing different just a spacer to take up son of the 700-r4 shaft length I didnt take it apart I just took the seals. I tried removing both driveshafts put it on thw lift and tried it and it still does it so im starting to think it must be a bad internal bearing?

 

[77k5]

It did retain the front input bearing nothing different just a spacer to take up son of the 700-r4 shaft length I didnt take it apart I just took the seals. I tried removing both driveshafts put it on thw lift and tried it and it still does it so im starting to think it must be a bad internal bearing?

Put the front shaft in and take it for a spin.

 

[onetoncv]

what are your angles ? Steve is right it could be gear rattle . Jess

 

[l.jpeterson]

Angle is pretty steep its in my 88 wrangler that has all chevy drivetrain. Its just a standard yoke top and bottom single u joints.

 

[l.jpeterson]

Here is a picture of my transfer case yoke and driveshaft as you can see its pretty steep

 

[onetoncv]

I hope that's a full droop ? That's the problem if its not, you have a 18 degree operating angle and need a c/v man and quick. Its gear rattle for sure. Jess

 

[l.jpeterson]

Yes that photo was taken at full droop, im thinking about posting in the jeep forum to see what I could do to stretch my rear. Part of the problem is the shaft is so short. Thanks for the responses ill keep posted with what I get figured out

 

[onetoncv]

Its always been the leading issue the wheel base for the rear shaft .

 

[l.jpeterson]

Ya might be hard to figure out because the rear part of my springs are "immovable" here's a picture of my setup attached