Took my jeep on its first wheeling trip over the weekend, had a blast, and came out mechanically unscathed.... or so I thought. I now have a leaking rear pinion seal which needs replaced, but today I started to feel, and if I listen carefully, hear something grinding from under my jeep. I only notice it in drive, and at low accelerating speeds. Once I get to about 10-15 MPH, it goes away, or is at least masked. I know it is from a rotating part cuz it is "periodic". By that I mean its like, "grind, grind, grind, grind" and gets faster (as I speed up), until it goes away. Any clues were to start looking? Thanks

 

Also I should mention that I have a very loud, and also periodic squeak coming from the front somewhere, which also gets faster as I speed up, but does not go away like the grinding feeling.

 

Since the pinion seal is leaking, the rear axle is the forst place to look. Pull the inspection/fill plug from the diff cover. The fluid should be at the bottom of the hole, or running out when you fill it. If it's pow that could be either the gears, of the bearings in there making the noise.
You should really remove the diff cover to inspect for any metal shavings in the fluid, and check it's condition, as well as check the gears and to see if there's any visible damage. Also check the carrier assy.
I'd replace the pinion seal if there's no damage present, then replace the cover and refill. Running it low on fluid will cause damage.

 

That could be either the u-joints, or the brakes. IMO

 

I checked the plug on the cover, the fluid was a tad low, but in good shape. I will keep filling the diff with fluid until I get around to fixing the seal, which hopefully will be in the next 2 weeks. I could feel the grinding in the floorboard by the pedals, so I have a feeling it is coming from the front, but thats just a hunch.

I'm gonna clean my jeep off to find out if its the brakes or not. I will inspect the ujionts then too.

 

Did you check the fluid in the front diff too?

 

No.... why, to see if its low, and thats where the grinding is coming from?

 

That's my thought.

 

Good call, I'll check tomorrow.

 

Okay. Keep us posted.