951JEEP

07 JKU. I have been experiencing intermittent transmission slip (so I think?) for about the last 3k miles (I just rolled 100k). I have a 2.5" TF coil lift and run 35s. Typically when returning home and wanting to back into the garage (small incline) shifting from drive to reverse the JK 'bucks' sometimes a few times before it stays in gear and makes its way into the garage (about 30' in reverse). Today, however, I came home put it into reverse and got about 15' up the driveway and felt it buck accompanied by a loud clunk and grinding noise. Now the JK will not shift into drive or reverse. If its in neutral with the engine on, it will not budge. I have been attempting to push it into the garage by means of turning the engine off while in neutral. I checked the trans. fluid level @ nominal temp and its topped off; fluid is red is color with no smell. Looking under the JK with my wife in the drivers seat, the linkage moves @ the tranny in all positions. I had the transmission serviced; flushed/filled @ 90k.

I have been told the neutral safety switch causes all sorts of problems...but I'm wondering if its more than that. Im literally stuck...my only blessing is that it happened @ home and not somewhere else.

Any insight? I don't even want to guess at how much a repair is going to be as I have been quoted the NSS parts/labor is approx. $500.

ronjenx

My first thought was fluid level, but you covered that.
Second thought is ...Did you re-gear after installing the 35" tires?

951JEEP

yes. I re-geared less than 1k to 5.13.

UPDATE: with the JK in Neutral, engine on or off....the transmission seems to be 'binding'. I can no longer push the damn thing. While in reverse, the transmission sounds like a gear is just spinning.

ronjenx

Have you tried pushing it with the t-case in neutral?
With the bucking and clunking noise, I'm wondering if it may be the t-case.

Was the grinding noise more of a ratcheting noise?

951JEEP

I pondered the damn transfer case. To be honest...it could be one or the other..or both? How do I manually shift the transfer case into neutral? I suppose the noise could be described as ratcheting....

ronjenx

Ratcheting could be the parking pawl, if the shift linkage is out of adjustment.

Ratcheting could also be the splines in the t-case if that linkage is out of adjustment. Sometimes it's broken.

If the JK is on an incline, chock the tires.
Put the t-case into neutral with the t-case lever. Pull it from 2wd, through 4hi, into neutral.

951JEEP

Sorry..brain fart. Im back in business....sorta. With the t-case in neutral, I am able to push the damn thing again. With this being the case, what do you suspect the cause could be?

BTW...it was a mother F*kr to get it shift. I ought it with 76k on it...and now I am questioning if the case has ever been serviced?

ronjenx

The t-case will be hard to shift if there is a load on the drivetrain. If you were still on an incline, and it was not rolling on it's own, the driveline has some torque on it.

951JEEP

I had the JK at the foot of the drive way where its pretty level. It was stationary with the trans in neutral...still a PITA to shift the t case into all positions. Makes me lean more towards the t case. Definitely appreciate pointing out placing the t case into neutral.

ronjenx

Don't think of the t-case being hard to shift as a symptom of it being bad. When not in motion, the splines inside may not be lined up, making engagement difficult. Going into 4lo can be very difficult, even on a perfectly good t-case.