Wrong, 4 minutes and 38 seconds is the norm. <img src="/forums/images/graemlins/smile.gif" alt="" />

Also of note, if you read my swap thread where I believe it was stockraider followed suit, and swapped the Early SR Diff into his, the pics he posted, the locating rig on the Driveshaft yoke on the early unit was larger.

Best bet with this here early SR diff is to pony up a hun or so and go custom driveshaft.

If you dont want to get stuck, lock the rear end. An LSD is nice but nothing compared to a rear locker. If your hanging up on the flange, you got bigger problems, ie you were gonna get high centered on the diff anyway if you kept going forward...

Also, before you get too far into this, ensure that the thing does not leak. If it does wait for another unit to show up.

Energize the pump with 12V. It should come to pressure then shut itself off and hold for at least a minute or so before coming back on to re-pressurize. If it keeps cycling, the locker diaphragm has a leak.

Gotcha.... thanks.

Frank

It seems to me that it's the pinion shaft that's the kicker, not the flange. Is the early 3.5 pinion spline diameter/count the same as the 3.0?

I don't know. I also don't know if the pinion shaft diameter is smaller on the later locker. It would be interesting to see the 2 units side-by-side to compare them.

It makes sense that the 9.5" rear would have a larger diameter pinion shaft, so it's entirely possible - maybe likely - that for the later lockers, Mitsu simply turned the companion flange to a smaller diameter and mated it to the smaller yoke and u-joint.

My question is "Why?" - maybe for the same reason I see with the amount of flange protrusion? Or was it so they could minimize the number of parts they made across all product lines?

It would seem that the larger yoke and companion flange would be stronger - but if it experienced a higher incidence of strike damage, the failure rate might be more than the smaller unit.

As has been said, the problem is probably more imagined than reality..... particularly if the truck sits in the garage. <img src="/forums/images/graemlins/lol.gif" alt="" />

Frank

The SR pinion flange is the same part number from 12/1993 till 1999.

OK - I was confused - I see now that the flange yoke bolt pattern is the same - just the u-joint receiver end is smaller.

Frank

That would appear so. Mitsu does not have a PN for the yolk, just full shafts.

I do see the 1997 looks to have a CV joint on the front end of the shaft. That is interesting.

I never did measure the pilot on the flanges today, sorry. I will get that tomorrow.

Damn Land Rovers get in the way. Oh yah that was paying work.

I'm telling you, a lot of us have done a lot of research on this upgrade. It all boils down to this.

Measure the u-joint on the SR and compare that to your truck. They use the same joint.

If they are the same, bolt the rear into place, if they are different, wait for the right one or modify the drive shaft.

It's that simple.

PS. we went though that flange thing, pinion thing, drive shaft thing............ I bet if you did a search you would find more information than you'd ever need. There is even information on the new 4x4 wire portal, but for the Gen II.

Just measured the pinion shaft end diameter on the locking diff I have with 4.272 gears (assumed '97+) and it's 22mm. The shaft diameter on the '97 open diff I have is the same. If that helps.

However...what Michael said <img src="/forums/images/graemlins/kewl.gif" alt="" />