Best 3 speed transfer case? (1 Viewer)

[IDave]

I know this has been discussed before, but the search brings up so much that it is overwhelming to find what I want. So I hope you'll forgive me for asking again.

I want to rebuild the transfer case in my pickup. To minimize down time, I thought it would just as good to rebuild someone else's, then install it (along with the transmission. I already have a rebuildable transmission spare.)

So, I was wondering which year cases are the toughest. (and if anyone has one of the appropriate year which they would be willing to part with somehow).

Also, current thoughts on rebuild kits for both cases. I remember once reading about a best source for a hardened idler gear shaft for the transfer case, and am interested in that as well.

 

[Trollhole]

http://www.kinzers.com/don/landcruiser/tcase_tech/

 

[3_puppies]

Dave, I've got one from a 72 here in helena. are you going to keep the vacumn shift?

 

[IDave]

Yep, definitely want the vacuum shift. A 72 looks like it would fit the bill perfectly!

I'll PM you.

Thanks for the link, Trollhole. That was perfect.

Anyone have thoughts about rebuild kits?

 

[3_puppies]

dave, that link and other info is in the techlinks. Paul

 

[IDave]

Thanks, Paul.

 

[Pin_Head]

The differences in the cases and idler gear shafts may be more apparent than real. I believe that is is John Pardi's opinion that while the early 3sp cases were made of a more brittle alloy it doesn't mean that they are weak. The same force that will stretch a soft case will crack a brittle one. Although I don't have as much experience with cases, most of the ones I have seen break are the later ones, but they are more common.

The lore is the Toyota OEM shafts are harder and therefore better. My experience is that the OEM shafts tend to spall, while the after market ones wear. Niether one is great, so take your pick.

 

[IDave]

Hmm. Crumbling shaft doesn't sound good. But what bugs me most is the whining.


I doubt that I'll be putting this case much into harm's way. I'd just like it to last.

 

[andrewfarmer]

To help save the case, drill an 8mm hole through the centre of the idler shaft.
Make up a washer of each end (with an 'o' ring in the face).
Put a long cap screw and bolt up tight. (this replaces the old 'tab' that previously mounted the idelr shaft.

This helps prevent the case breaking. A lot of the problems are caused by the cut of the gears trying to force the idler out of the back of the case. The bolt throught the centre transfers these loads to both sides of the case, in theory making it twice as hard to break.

Worked for me.

 

[Pin_Head]

Hmm. Crumbling shaft doesn't sound good. But what bugs me most is the whining.


I doubt that I'll be putting this case much into harm's way. I'd just like it to last.

Both shafts are probably good for at least 50,000 miles. If the bearings and bushings are good and the gear teeth aren't worn from years of running with bad bearings, they don't whine. At least the ones I have had didn't.

 

[65swb45]

Dave, once the case has a whine, it is there to stay. You will get a lot of peace of mind from the rebuild, but not a quieter transfer case.

I prefer the earlier cases.

 

[bad_religion_au]

search newbie

kidding

 

[IDave]

Dave, once the case has a whine, it is there to stay. You will get a lot of peace of mind from the rebuild, but not a quieter transfer case.

Really! Why is that, Mark? I've read that one of the main whines comes from the idler gear shaft, and I must say that my FJ40, which when I started with it, was at least as loud as my 45 is now, is quieter at least by 20 decibels following the rebuild I did on that.

But then, it is definitely quieter than it was a month ago. I've put on more miles in the last 2 months than it has most likely seen in 20 years, and I wonder if I am just smoothing off some corrosion.

I know the transmission needs work, because there are NO syncros, so I thought I'd just redo the transfer while I'm at it. I can hear the T/O bearing in there, too.

 

[IDave]

search newbie

kidding

Help me out with some links, bud

 

[cruiseroutfit]

To help save the case, drill an 8mm hole through the centre of the idler shaft.
Make up a washer of each end (with an 'o' ring in the face).
Put a long cap screw and bolt up tight. (this replaces the old 'tab' that previously mounted the idelr shaft...

Pics?

Anyone else done this?

I agree about the gear walking...

 

[65swb45]

The whine comes from the incorrect interface of the gears to one another, a distance that is set fairly precisely at the factory and has changed over time because of wear. Same way ring and pinions develop a whine when they are run with a loose pinion bearing; that noise will never go away either.

When the gears are allowed to move closer together because of sloppy or worn bearings and shafts, the extra friction and resulting heat start to polish and reshape the face of the gears. The more polish, the more whine. Changing bearings and shafts does not change the polish of the gears.

 

[65swb45]

Pics?

Anyone else done this?

I agree about the gear walking...

Let's think this through. If I understand the suggestion correctly, this would involve using washers on BOTH sides of the case, front and back. I have seen many cases and idler shafts that were worn on the front side of the case, so the prospect of stabilizing it would be attractive.

That said, I do not think that this would work. First off, on the four speed trannies, there is simply not enough room for anything larger than the stock freeze plug on the front side of the case.

Second, driving the idler in from the backside of the case to bring it close to flush on the front side would mean giving up the keyway that keeps the shaft itself from turning. Trusting that shaft to stay still, especially with an o ring between the shaft and the flatwasher [as recommended] makes it dubious that the shaft could be stabley held for any length of time

And, as far as the cracking goes, it starts from the top, inside corner, because of a flaw in the casting and a general weakness of radiused corners.

 

[cruiseroutfit]

Good Tech

 

[andrewfarmer]

I'll try and get some pics.
I've done it with my 4spd t/case and H41.
Been like that for 2 years now with no problems.

 

[IDave]

Good Tech

So, Kurt, does your kit contain the hardened OEM, or a soft idler gear shaft?