Problems on my 87 XJ w/ 470K Miles

[GPN 05]

I know I have posted many times about My XJ's... but for some ppl who really know the answers here's some questions for ya !!!

Sometimes... Usually out coming out of 4x4, coming down from high speeds 60-80 MPH and then accelerating to 50's 60's again... the truck acts like it's slipping, or jerking... sometimes just a few times, others just feels like a rumble... What is it ?

I'm pretty sure I have figured the next question out... But here it is anyways...

I have a click in the right front wheel structure... IT'S NOT CV or U JOINTS.... Could it be my Wheel Caliber or Rotors ?

Then the last question would be when starting the vehicle (after it's had time to drain the oil back down) and high idle the engine makes a rumble sound like it has a wrench in it or something.... Was told could be main bearings, or Fly Wheel or Flex Wheel... What is it ? and how do I fix it ?

Thanks Again

Corey

[JeEpBoY95]

that slipping could be your transfer case chain but i'm not sure how to tell for sure. Replacing the T-case chain is also a pretty involved because you have to take out and split your t-case. If it is the chain it will rub against the housing and eventually break through which is a very bad thing.

[GPN 05]

Why would a chain slip though ?

[muzzleloader113]

My chain stretched and sounded as if it waas grinding when I depressed the accelerator. I changed the transfer case and opened the old one. I found the contents to be all mechanical chain drive (srt of like the gears on a ten speed bike). If you let it go to long, the chain will come off the sprokets and grind all the meatl inside to peices, as mine did. Drain your fluid and check for metal debris. If so you will have to replace it. It is to expensive to rebuild. Cheaper to buy a junk car and strip it for parts. Good luck.

[jeep!_r]

GPN 05,
Not sure of what to tell you on doagnostics, but if you've got 470K then its getting up ther eon drivetrain. Anyhow, just thought I would tell you that if you do look to replace the t case be sure you're getting the right one. They built to differnt ones...a new process 231, and np 242. The NP231 is the most common, and utilizes the vaccum motor on the front axle. The NP242 does not have this motor, and has a $H part time, and a 4 high full time. The np242 is a better t case. Just thought I would throw that in
B

[debb718]

the chain would slip due to too many miles on the chain they are only good for like 100k