Rear End Noise

[Wranglerman21]

Hello Jeepers!! Well I have a 2001 Wrangler with a dana 44 which had a leaking pinion seal. I replaced the seal, took the rear diff cover off to change the fluid and put it all back together. I put 75-90 mobil one gear oil back in the diff and sealed up the cover. I changed the pinion seal and when i put the Pinion Nut back on i torqued it down to 210 ft lbs. Im not sure if thats the correct amount. (my haynes books doesnt say OFCOARSE) Now when im going down the road and there is torque on the rear end its got a wining noise, but only when power is applied. I wasnt sure if i torqued down the pinion nut too much wrecking the bearing. Anyone have any guesses??? Help is greatly appreciated fellas!p0p

 

[SteelHeadz]

SPECIFICATIONS
AXLE SPECIFICATIONS DESCRIPTION SPECIFICATION
Axle Ratio 3.07, 3.55, 3.73, 4.10
Differential Bearing Preload 0.1 mm (0.004 in.)
Differential Side Gear Clearance 0.0-0.15 mm (0.0-0.006 in.)
Ring Gear Diameter 216 mm (8.5 in.)
Ring Gear Backlash 0.12-0.20 mm (0.005-0.008 in.)
Pinion Gear Standard Depth 109.52 mm (4.312 in.)
Pinion Bearing Preload - Original Bearings 1-2 N·m (10-20 in. lbs.)
Pinion Bearing Preload - New Bearings 2-4.5 N·m (20-40 in. lbs.)

TORQUE SPECIFICATIONS DESCRIPTION N·m Ft. Lbs. In. Lbs.
Fill Hole Plug 34 25 -
Differential Cover Bolts 41 30 -
Bearing Cap Bolts 108 80 -
Ring Gear Bolts 108 80 -
Pinion Nut 217-271 160-200 -

 

[Collin the Hen]

From what I've studied, you should never reuse a pinion nut. If it's whining, chances are the gear pattern if off. As far as your bearing, you're probably fine since the above info says 217-271 for the nut. Also, bad bearings sound more like airplanes than whining(at least in my experience).
I guess you could buy a new pinion nut and torque it to specs, and see if it still whines. I'd let someone else confirm my advise first, though; I'm still studying gear setups.

 

[Bounty__Hunter]

I'd bet bad pinion bearings caused the leaky pinion seal in the first place.

 

[Wranglerman21]

Well now that you say Airplane noise..................thats exactly what it sounds like. but only under power. And i guess that im comfused on why my pinion nut would make that noise. Im not saying that anyone is wrong b/c i dont have the slightest idea and all of your help is greatly appreciated.

 

[Wranglerman21]

How hard is it to do a pinion bearing?? DOes that mean that my rear pinion seal is going to have to be replaced again?? Thanks again guys

 

[Utah_jeepster]

When you re-tighten the pinion nut you don't need to take it to 210+.
First you need your rear end in the air and loosen and re tighten the pinion nut till you get 15LBS of "turning" resistance on the torque wrench.
My guess is you over tightened the pinion bearings and over tightened the required pre-load.
The 2001 Dana 44 rear end came with a special nut that digs in the yoke to lock it place. Also the pinion is a non-crush sleeve type and you set the pre-load to the 15LBS turning resistance only.

When I installed my ARB this was strange to me since I was used to crush sleeve type of pinion axles.

P.S. I was chatting with my mechanic/jeeping buddy and he recommends that you open the rear and visually inspect the bearings and the two slingers to make sure you didn't crack them when you tightened the pinion nut.

 

[Wranglerman21]

Thank you so much utah jeepster. That was a big help. I think thats what im going to do............how hard is it to change the pinion bearing??? anyone know???