4wd making noices

[coach]

New guy here. Weather just got semi-bad and needed to go to 4 wheel drive for the first time. Locked the front hubs and away we went. Everythings fine until letting off the gas &/or down shifting, and there is a vibration/grumbling sound coming from, what I suspect, is the front drive train.

LC Docs...... what's my cruisers problem?

Thanks in Advance!

 

[Wile E Coyote]

First place I'd look would be the health of the u-joints, followed by the pinion preload.

 

[coach]

Would it have some play in the joints or would it need to be taken apart to inspect? I am not real experienced with these things but have a lot of common sense.

The Pinion........no idea. I will check my Tech Manual.

Q: I have a slow leak of something, not oil, in the front of the truck. Could it be a fluid level issue? If so, besides Oil, Brake Fluid, and Antifreeze, what else is up front?

By the way, the truck is 1990 FJ62 with the 5 speed conversion. I guess I should have put this info in my original post, sorry.

 

[Lost]

go under your truck and check for free play where the drive shafts are bolted to ->transfer case and axles.
check u-joints for damage while you're there as wile e coyote recommended

 

[alaska60]

Grab your drive shaft and move it or spin it by hand while its locked to check for play in the U- joints. It will have play if the joint is bad. Easy fix if thats the case.

 

[coach]

Thanks guys, I will post my findings as soon as I can roll around under the truck. If it is U-joints, are these something that can be repaired at home? I have replaced them before back in college....20 years ago! Yikes! It was pretty easy on my Ford pickup. I am so new to these LC's, and admit I am addicted, loved them since I was a kid. So I bought one and kept it for a few months, then another. I am sure from this forum that I am in like company!

Side questions.....will 33x12.5's fit on the stock rims? And where can one get a rear tire mount?

 

[RockDoc]

Thanks guys, I will post my findings as soon as I can roll around under the truck. If it is U-joints, are these something that can be repaired at home? I have replaced them before back in college....20 years ago! Yikes! It was pretty easy on my Ford pickup. I am so new to these LC's, and admit I am addicted, loved them since I was a kid. So I bought one and kept it for a few months, then another. I am sure from this forum that I am in like company!

Side questions.....will 33x12.5's fit on the stock rims? And where can one get a rear tire mount?

33x12.5s will fit on stock rims, but I wouldn't recommend them on stock rims for on road. Could be a safety issue, and you'll get a poor wear pattern.

BTW, my truck hums/growls at speed with the 4WD engaged, but more under load than coasting.

 

[coach]

I drove the kids to school today and gave it another try seeking more info. Correction, it doesn't make noise during coast, only when in gear decellerating. As soon as I give it some gas it stops doing it.

BTW. I know that this LC will go where my Excursion can't, but man it sure sucks on ice compared to my Excursion. Southern Indiana was an ice ring this moring. I am assuming it's because of lack of Traction Control, am I correct?

 

[Randy88FJ62]

Would it have some play in the joints or would it need to be taken apart to inspect? I am not real experienced with these things but have a lot of common sense.

The Pinion........no idea. I will check my Tech Manual.

Q: I have a slow leak of something, not oil, in the front of the truck. Could it be a fluid level issue? If so, besides Oil, Brake Fluid, and Antifreeze, what else is up front?

By the way, the truck is 1990 FJ62 with the 5 speed conversion. I guess I should have put this info in my original post, sorry.

You mentioned a leak; Please take 5 minutes and take the top filler bolt out of your front differential and put your finger in there. If you can't feel the differential oil with your finger then it's low. A bad pinion seal or knuckle seals would let it leak out. Better to refill it that seize your front differential.

 

[lehiguy]

If your rig is lifted at all, be that with springs or even shackles, driveline angles will change and some growling form the drivelines may happen even if all the hardware is tight.