requesting help of veteran Tcase rebuilders

[alaskajosh]

I appreciate the help.. I need to get this back on the road by early this week!!

Putting my SIII Tcase back together with the help of the LR Workshop manual.

They call for an end-float of .006-.008 between the high gear wheel and it's thrust washer (held by the circlip). Fine.

But then when I set the pre-load on the shaft bearings, using the speedo housing shims and according to 2-4lbs on a spring scale, that end float on the high gear turns to nothing and it becomes quite tight on the shaft.... too tight to turn on the shaft very easily let alone get any feeler gauge in there.

I fear that it will cause a lot of friction/wear and be difficult to engage high range.

Thanks again, gents!

King regards, Josh

Edit: At 1:30am I just finished reassembling. I think the problem was the flimsy (new) Genuine Parts circlip just couldn't take the load and was jumping out of it's groove some. I replaced it with the old circlip (which was worn and had one of it's ears busted off) and things seem to be okay now(???).

[Daurie]

I dont know if you're totally reassembled yet but two things come to mind here. One is, it's quite possibe the new circlip never seated properly and was causing the binding and eventually popping out. I've run into some pretty tight fitting clips and sometimes light persuasion with a soft face mallet is required. The second thing that comes to mind is, if there indeed is an issue with the circlip I'd try another from another source. Most parts houses or good hardware stores will have circlips. If its a big one try a place like truck pro or a heavy equipment dealer. It could be the new clip needs to be thinned out slightly. Easily done with a flat surface, fine grit sandpaper and some thin oil.

Regardless, the thought of reassembly with a broken and worn one would cause me some concern.

Good Luck
Daurie

[Daurie]

After looking through the manual from what I can tell you adjust the end float by reducing the thickness of the thrust washer. If things fit properly with the old clip thats worn I would suggest making the adjustment with the thrust washer and making that new clip fit. What parts did you replace in the T case? Or what was the cause for rebuild?

[alaskajosh]

Thanks for your reply, Daurie!

It's all back in now and back on the road. So far, so good.

I undertook this job to swap in some "Suffix B" gearing for the lower low range. I ended up replacing the high gear, low gear, intermediate pinion, and intermediate pinion shaft as they had been "run in" together in the donor case.

The first oddity I encountered was trouble achieving the end float spec'd on the high gear. Where the manual calls for .006"-.008" of float (with the circlip pushed down against the thrust washer and gear) I probably had closer to .012" or more!
Excessive float.

I know the manual says to correct this with a thicker thrust washer, or gear, or shaft (!). But I had a couple of gears and a couple of thrust washers which all mic'd within .001" of each other so it didn't seem likely that they were worn down. I could still see the light machine marks on the bearing surfaces... not likely worn out of spec.
I doubted, too, that my shaft was worn away that much. Nor was I interested in buying a new one!

RN was out of thrust washers and I really had no reason to believe that a new one was going to be .007" or so thicker than the ones I had anyway.

I did buy a circlip from a local source but it was the same flimsiness as the new one from RN. Ultimately I reassembled using the old (better) circlip.

Once I set the pre-load on the bearings that endfloat on the high gear had squeezed down to almost exactly .006". Go figure-- I really think it's going to be fine.

Thanks again, Daurie, for taking the time to check it out, think about it, and respond!!

Kind regards, Josh