Rear diff pinion seal

[mulover]

Hey all, was just looking at my manual and it says use a pre-load guage to measure the force it takes to turn the axle drive pinion.

Have been asking around the tool supplyers and they can't find anything for me so i was wondering if anyone has one of these tools or knows where i can get one, or if there is another way of measuring the required figure.

I also need a new locking nut so if anyone knows where i can get one of them from it would be great!! thanks.

[James W]

Whats the pre-load supposed to be? is it in Ft.lb's? or whatever, ya just need a lever of a known radius and a fish scale, one foot pound is one pound at one foot radius. etc.

[Garth]

Sounds like just a torque wrench with a dial type indicator, Ie the more force you use the more the dial turns around indicating how much force it is taking to turn the pinion. Most car parts shops will have these on the shelf. From memory my rear diff pinion was torqued to around 300 ft lbs. still going great.

[mudgrip4]

A word of warning from experience.

It is critically important to be exact with torquing of the rear pinion locking nut - must be precisely to manufacturer's spec. Took mine into local garage couple of years ago to replace a leaky rear pinion seal and they got fitted this part and did not torque the nut correctly. Just 6 weeks later and all sorts of humming had begun in the rear diff. The spacer inside had collapsed under too much torque, then unbalanced and stuffed the bearings. Result: court case which I won, and a good second hand lsd from Truckbits in Akld. Which has actually helped the truck no end.

A b****** of an experience from which it is very clear you can't guestimate the foot/lbs. Get this one absolutely dead right, as the inner spacer is the weak point and quickly stuffs the diff. Replacement and resetting of pinion and carrier bearing set quite expensive. Not a mechanic but this is the one job I now get the Isuzu specialists to do. And they get it right.

Hope this forewarns.....Mike

[geeves]

If you dont replace the crush washer you can mark the housing and count the turns but if you get it wrong then wave your diff bye bye as mudgrip stated. This bolt also sets the preload etc on the gears. Normaly the preload is measured with a straight spring balence attached to a predefind place ie pinion flange bolt hole and a straight pull is used to rotate the pinion.

[mulover]

The torque value is however much it takes to turn the drive shaft with the old seal still in, plus .5 tp 1.1 ft/lbs extra. In the manual they say to use a preload guage, but still can't find one. When i did the front one i set my torque wrench to its maximum and tryed to turn the nut, it wouldn't move, so i undid the nut and did it back up again untill the torque wrench said enough. It all seems fine, no leaks, no noise, but i want to get the rear one right since it has alot more load on it. I'll keep looking or else take it somewhere when i've got the axle out!!

[geeves]

3. Adjust pinion bearing preload.
a. Measure the bearing preload by using a torque
meter. Note the scale reading required to
rotate the flange.
b. Continue tightening flange nut until the
specified starting torque is obtained.
Starting torque:
New bearing
0.7–1.3 N·m(0.07-0.13kg·m/6.08–11.28 lb in)
Used bearing
0.4–0.6N·m(0.04–0.06kg·m/3.04-5.64 Ib in)

using www.onlineconversion.com/torque.htm this converts to 0.94 ft pound for the highest measurement.
A realy realy good torque wrench should be able to do this. The picture looks like a small torque wrench. A look though engineering catolouges alse came up empty

the nut looks like a holden only part

[mulover]

The nut is a holden only part, $25 and 3 weeks from japan!!!!!
I think i might have to buy a fish scale like james said, or just take it to the hydrolic shop and get them to do it!!!