New Whining Theory (1 Viewer)

[warpdriv]

There has been some discussions in some other threads about how some people's, including myself, 80 whine above certain speeds.

After reading a comment that Cristo said, got me thinking.

What is the mechanism in the transfer case that regulates the 4H power distrubution? Is it clutches? So if this mechanism went out of spec and needed a rebuild, would unevenly distribute power to the point to create whine?

I am not familiar with the inards of the transfer case, but I thought I would start a new thread.

What do y'all think? ???

 

[Beowulf]

Jeff,
If you're interested in the innards of the transfer case landtoy80 (Kurt) has posted several pics in a thread in the archives. I can't recall a search word but if you try "shaft" or "bearing" with landtoy80 as the author then you will probably get the post. (Adv search, 300 days)

FWIW, I don't think any of us have figured out how the 80 VC transfer works... at least nobody has come out and said they are able to explain how it works.

-B-

 

[Beowulf]

OK, I did the search. (Shaft & Landtoy80)

Here is his post with all the pics

-B-

 

[IdahoDoug]

Jeff,

The simple answer to your question is no - wear would not change the torque distribution which is 50/50. Even if it did, uneven distribution does not de facto create whine. I think the whine is simply a bunch of heavy gears in large metal boxes - one of them happens to be in a frequency at your speeds that it's noticeable. No biggie.

DougM

 

[warpdriv]

Thank you Beowulf. That's a great post. 8)

Doug, the more I thought about the VC, the more I agree with you.

The quest continues...

 

[IdahoDoug]

Jeff,

Having said that, I can say with a small sample size that my drivetrain is markedly quiet compared to other 80s I've been in. I attribute this to having switched it to synthetic when it was new and regularly changing all fluids. The gear contact faces got properly broken in, then the synthetic/fresh fluid strategy is keeping the contact faces from changing much. The noisiest are the '93s because Toyota added more soundproofing around the tranny/floor area during the production year. I'm pretty sure mine does not have it. CDan may have specifics on this.

DougM