Funny thump noise from front left hand wheel, when crawling

[jcianci]

I have a little bit of a queery for the jeep experts, i have a 96 jeep cherokee, with a 4 inch lift and 31 claws. Whenever i climb approx 20degree incline and up, i get an intermittent thump which sounds like it comes from the front passenger side of the car, it doesnt do it with the rotation of the tyres, its just now and then, im curious what it is. Any ideas?
:idea:

[greg188]

Does it occur when you turn with a a little force? It took a while to find and it turned out to be the bolt that held the lower trailing arm wasn't tight enough, allowing it to slide backwards and forwards in the hole. It was still really tight and took a lot of effort to tighten up more, but it was just loose enough to that when a bit of force was applied it moved.

[jcianci]

I got under the front end today and tried to wiggle everything around. I found out that the front slip yoke had play up an down, probably about 2 mm.
So i got the grease gun and pumped a stack of grease in and now there is no play at all. So ill find out if that was my problem when i take it out to the trail next. I dont think it is the lower control arm because i have shims behind the arm to stop it moving, and it cant move forward becuase it is at the end of the slot.

Thanks for your help buddy.

[optical]

mine does the same

i suspected engine mount ?

[jcianci]

try to wiggle your slip yoke up and down. I think if it was the engine then it would only do it when there is a change in torque, which is fairly constant when crawling. I guess ill just have to wait until the next 4x4 run. Ill keep you posted.

[Steve F]

Replied to this on OL, check the control arm bushings, my upper arm bushings are worn and I get a thump and also a cracking noise occasionally.

Cheers
Steve

[jcianci]

its still doing it. :mad: im trying to wiggle the upper control arms but they arent budging, maybe i dont have enough strength to simulate what is happening when im climbing a hill.

[Steve F]

its still doing it. :mad: im trying to wiggle the upper control arms but they arent budging, maybe i dont have enough strength to simulate what is happening when im climbing a hill.

If they move by hand they are well and truley stuffed, there is a lot of load on those bushes when driving up hill.

Cheers
Steve

[jcianci]

yeah it turned out to be an engine mount. Thanks guys.

[optical]

me and rodgebone inspected our rigs and it seems both of mine will need replacing asap :(

[FredE]

Go see wooders he has cheap engine mounts less than 1/2 the price of OEM's

[optical]

thanks for the suggestion frede :)

[brizXJ]

Yep..damn left hand one....heat must bugger it....Jeep make their money outa selling left hand XJ engine mounts!!

[Nevermind]

How much play in the slip yoke is ok? mine has 2-4mm play.