New IFS 4wd w/NP246 Issue

[DA BIG ONE]

As I wait for ARP to send parts to fix the excessive pressure in the IFS which causes the gear lube to blow out at highway speeds, I now discover that my front driveshaft, ring, & pinion all are rotating in neutral, like it is not disconnecting.

Again the ARB differential is suspect, and no real feedback from ARB, maybe because of holiday season.

I now wonder if this rotation will damage my new NP246 t-case beyond repair too?

[ 12-30-2004, 09:07 AM: Message edited by: DA BIG ONE ]

[Phil Holmen]

So when you are supposed to be in 2wd you can't spin the front driveshaft by hand??

[DA BIG ONE]

Originally posted by Phil Holmen:
So when you are supposed to be in 2wd you can't spin the front driveshaft by hand?? Nope!

[More Power]

Need to determine whether the txfer case is in 4WD or if the front diff in engaged - or both...

Jack up one rear tire, then see if you can rotate the rear driveline when the trans is in neutral. If the transfer case is in 2WD, it won't try to spin the front shaft.

MP

[DA BIG ONE]

Originally posted by More Power:
Need to determine whether the txfer case is in 4WD or if the front diff in engaged - or both...

Jack up one rear tire, then see if you can rotate the rear driveline when the trans is in neutral. If the transfer case is in 2WD, it won't try to spin the front shaft.

MP The front diff engages/dis-engages properly, t-case is somehow engaged at the clutch pack always thus spinning the ring gear. The case shifts ok between 4hi, 4lo, auto, but it does appear the clutch pack driving the front wheels does not disconnect.

I have e-mailed NEW PROCESS, and the distributor I bought the new case from to see if they can help here.

Little, or no info on the web on this AUTOTRAC as far as troubleshooting goes.

[DA BIG ONE]

Latest, When in auto 4wd the t-case is engaged always, try to shift out of auto 4wd and it will not.

Shifting in and out of 4wd hi, and 4wd low seem to be ok.

[DA BIG ONE]

Feedback from New Process; Clutch pack is always engaged on the NP246 in the GMC, the auto 4wd is controlled via computer by engaging front axles when speed sensors detect slip, or change of rpm at any wheel.

So, The front driveshaft is always live unless t-case is in neutral. T-case has 3 positions 4-hi, 4-lo & neutral w/controller operated autotrac.

All ARP parts (extrene duty kit) are a shop so after the new year I will hopefully get the issue of pressure buildup in IFS differential fixed.

HAPPY NEW YEAR TO ALL!

[DA BIG ONE]

Finally, fixed w/ addition of all new "o" seals, and air locker purge valve. According to ARB only their off road race trucks ever needed this purge valve setup, and now have it available for those rare occasions when us non-racers need a fix.

Back to synethic "purple" fluid too.

Off road manners better than expected, but wants to go only straight if you let it.

[cruzer]

Originally posted by DA BIG ONE:


but wants to go only straight if you let it. [/QB]That's what happens w/locking diffs!!!!!!!!!!