3 Speed Gurus!

[ibinazbass]

Hello all,

Calling the 3 speed transmission/transfer case gurus! I recently rebuilt both units. I replaced the ball & tapered roller bearings. seals. gaskets, and synchronizers. I have driven maybe 100-200 miles since and decided that the whine I have did not improve and thus I ordered a new transfer case idler shaft and bearing set in hopes to remedy some of the gear whine. When I removed the transfer case the second time around I drained both fluids and found an excessive amount of metal in each unit. I believe the metal came from the metal in the transfer case input seal. It has been rubbed on/worn down by something. Has anyone seen this happen?!

First off, the seal is fully seated in the transfer case. Secondly, the old seal was not worn down when I removed it for the rebuild.

I believe this could be related to the fact that the rear output bearing on the transmission is no longer press fit in to the case. It is easily moved in and out of the case though secured tightly to the output shaft. If I recall correctly it was not tight in the case before or after my rebuild. Am I correct in thinking that this bearing should be press fit into the case? Any recommendations for a remedy if this is true?

Second issue regards the gear whine in the transfer case. What should I be looking for to know if the gears are damaged beyond reuse. I am on a very tight budget and would prefer to not have to replace the gears. I was intending to replace the idler shaft and bearings and reassemble it. I'm at the point in my life where my money is far more valuable than my time. So I will gladly pull it back out again if the idler shaft doesn't fix it.

Appreciate the help!

 

[peesalot]

The rear bearing can be glued into the case with a product used on aluminum split cases to seal together, or other products, its not necessarily bad but not knowing how loose or if there is case damage hard to say , IIRC I had to glue it in on the original 3 spd case.

The seal rubbing is most likely caused by the lack of the spacer that goes on the trans outputshaft and keeps the tcase input gear from walking towrds trans.

IIRC when this happens the input gear of tcase will also rub the inside of tcase or get really close, I bet theres rub marks where gear contaced case?

 

[B y r o n]

Whine is usually a problem with the gears and not the bearings or shafts.

 

[ibinazbass]

The rear bearing can be glued into the case with a product used on aluminum split cases to seal together, or other products, its not necessarily bad but not knowing how loose or if there is case damage hard to say , IIRC I had to glue it in on the original 3 spd case.

The seal rubbing is most likely caused by the lack of the spacer that goes on the trans outputshaft and keeps the tcase input gear from walking towrds trans.

IIRC when this happens the input gear of tcase will also rub the inside of tcase or get really close, I bet theres rub marks where gear contaced case?

It was eaten from the transmission side. I will check the input gear when I get home on Tuesday.

For the glue, are you just talking about anaerobic sealer? Or what?

 

[peesalot]

Yeah, but on reflection I think it may be to much wouldn’t want to stick that outer in there for good and that stuff can do that. Another option is to use a sharp center punch and put a center punch knurl at 4 spots evenly to tighten that outer race, gotta keep it from spinning.

Are you sure seal was in correct ? If eaten on that side how would shavings get in tcase, Any pics of the metal in oil you speak of ? The first oil change after the rebuild can produce a bit more silvery sludge than one would like to see , I get it every time on the first change to various levels but still kinda a shock when you are hoping for clean,

 

[peesalot]

You have a pto gear or spacer ? If that stack is tight on the trans output from rear trans bearing to rear tcase bearing then the whole main shaft may be moving rearward, possible that the rear trans bearing is bad/installed wrong ? Did you get all the big c-clips on the bearings ?

 

[ibinazbass]

Yeah, but on reflection I think it may be to much wouldn’t want to stick that outer in there for good and that stuff can do that. Another option is to use a sharp center punch and put a center punch knurl at 4 spots evenly to tighten that outer race, gotta keep it from spinning.

Are you sure seal was in correct ? If eaten on that side how would shavings get in tcase, Any pics of the metal in oil you speak of ? The first oil change after the rebuild can produce a bit more silvery sludge than one would like to see , I get it every time on the first change to various levels but still kinda a shock when you are hoping for clean,

That's a good idea! I'll post pictures tomorrow

 

[Mark Jennings]

The rear bearing on a 3 speed isn’t supposed to be a tight fit in the Transmission, when you bolt up the T-Case, the T-Case holds that bearing in position.

 

[peesalot]

He was saying the rear bearing in tcase was loose

 

[ibinazbass]

No, the rear bearing in the transmission is loose in the case, I assumed it should be press fit. So I must be incorrect?

 

[peesalot]

oh, the previous post is correct, that is not a tight fit like the one at rear of tcase.

 

[Splangy]

We need pictures

 

[ibinazbass]

We need pictures

Yeah, I am a Paramedic and am on 72 hour shift right now. I get off in the morning and will get some pictures posted

 

[ibinazbass]

Pictures:

Did I just install the seal backwards? The ball bearing cage seems to be what has rubbed on the seal.

 

[65swb45]

The horizontal shadow lines across the facing of the gear teeth are what is causing your whine. The gears were run with compromised bearings, letting them come too close to one another. The noise will not abate unless you replace the gears with ones that do not have the shadow mark.

That said, it’s all relative. Even good 3speed cases whine, which is why they changed the design in the first place. If you want to put a 76-80 4speed case behind the 3speed transmission, I stock the crossover input gear for that swap.

www.marksoffroad.net

 

[ibinazbass]

The horizontal shadow lines across the facing of the gear teeth are what is causing your whine. The gears were run with compromised bearings, letting them come too close to one another. The noise will not abate unless you replace the gears with ones that do not have the shadow mark.

That said, it’s all relative. Even good 3speed cases whine, which is why they changed the design in the first place. If you want to put a 76-80 4speed case behind the 3speed transmission, I stock the crossover input gear for that swap.

www.marksoffroad.net

Thanks Mark! Correct me if I'm wrong but don't the later transfer cases have a higher low range?

Any comment on the seal wear? Do I just have the seal in backwards?

 

[peesalot]

I have never seen the bearing cage hit the seal, is the spacer between the trans rear bearing and tcase input gear in there ? Honestly at this point a call to Georg at Cruiserbrothers would be the fastest way to solve problem.

 

[ibinazbass]

I don't think I have a spacer to put between, nor have I ever? I don't see where that's listed in parts diagrams or the service manual either.

 

[ibinazbass]

I have never seen the bearing cage hit the seal, is the spacer between the trans rear bearing and tcase input gear in there ? Honestly at this point a call to Georg at Cruiserbrothers would be the fastest way to solve problem.

To clarify, I do see the input gear stopper/spacer on SOR, but it says it's for 1973+

 

[65swb45]

@peesalot has 4 speed on the brain. No spacer on the 3 speed. As for the seal, did you apply lubrication when you assembled it?