Transfer case slack?? (1 Viewer)

[Herbert]

Hi all,
I'm tracking a '91 Fj80 on ebay right now. The guy anwered some questions I had, including this sentence: "It does have the typical 4-wheel drive transfer case slack that all have."
What the h*** does he mean? Any ideas? Is this really a common problem on the 80s? Or is it a problem at all?

Thanks
Herbert

 

[Romer]

I have never hear of it. I would change your sites to a 93+ (more horses) Go to slees website and review the newbie guide before you buy.

www.sleeoffroad.com

 

[RavenTai]

80's do tend to get some slack in the drive train over time, lots of wear points and since AWD all the play of those points stack up, a little is common,

But hard to tell from only text that is twice removed from the source if this play is normal or indication of expensive problems. You would have to look at it in person.

Search for threads about noise going from drive to reverse or vise versa

 

[landtank]

I've worked on a few 91/92 and there is some slop in there that is typical. On both trucks though a bad PS drive flange added to the slop but once replaced it didn't totally get ride of it. From what you have wrote the guy seems to be being staright with you and I'd suspect that it's the typical stuff. Most of us will do a drive by for you if we are near by.

 

[CJF]

It's common for 80's to have a sort of "slam-clunk" when shifting from reverse to drive or vice-versa, due to all the accumulated all time (geared) 4wd slop. We've discussed this on the 3FE list and have come to the conclusion that it's usually "normal" and not a sign of something about to wear out. My 91 has been doing it for over 100k now.

CJF

 

[slambson]

Mine has more than what I feel is normal. Alot of hard driving and a bit of ATF in the transfer case don't help. I drove a 92 with 140K on it last week. Still a bit of play but less than mine. I've got a transfer case with 60K on it sitting in the garage for a weekend summer project. There is still some play in it if you twist the two output shaft oppositely.

Factor in the u-joints, differential and pinion, axles, birfield, flanges and there can be alot of accumulated slack.

 

[IdahoDoug]

Dunno if I'd agree with the statement that 80s have a common "slam clunk" when shifting. I've owned and driven a lot of 80s over the years and the only time I hear this is when someone's got dry drive shafts that haven't been properly greased. The drivetrain components are all overbuilt and with full time 4wd the torque's further split to 50 percent to a given axle - again limiting stress. I drove my bro in law's today with all original parts and casual maintenance and 290,000 miles and it has not even a clunk.

I'd ask more about this "slack" and how he arrived at it. The 91s are extremely reliable and understressed, so a decent one is a nice long term vehicle that will need only grease and oil to see very high miles.

 

[landtank]

So your brother in laws is a 91 or a 92?

 

[IdahoDoug]

It's a 93 and is as smooth as my 93 - which naturally pisses me off....


DougM

 

[CJF]

It's a 93

That's the point. Aren't 93+ T-cases fluid couplings (when open), while 91-92 FJ80's are true (gear) differentials?

CJF

 

[CJF]

Doug,

Re-reading your post, now I'm guessing that first "93" is a typo??

Curtis

 

[RavenTai]

This seams to be a common mis-conception,

the 93-97 HF2AV transfer case has a viscous coupler but it is not like other all wheel "t-cases" where one axle is driven only through the VC, the HF2AV has a full geared center differential and the front and rear drive shafts are splined directly to it, the front and rear shafts are also splined to a VC that dampens the action of the differential resisting differences in RPM front to rear, theoretically you could disassemble the T-case and remove the VC making no other changes reassemble it and still drive the front and rear wheels, you just loose dampening, and have basically made a HF2A (91-92)

I think this is why it says “Full Time 4WD” in the back instead of “All wheel drive”

 

[CJF]

RavenTai,

Cool info; thanks

Curtis
91FJ80
TLCA member

 

[landtank]

I asked Doug because the 91/92s are known, for whatever reason, to have more of this play in the drive line than the later years. What we are taliking about here would be abnormal for a 93+ vehicle.

 

[IdahoDoug]

Curtis,

Sorry, been out all day on another search (grrr - getting old) and didn't reply. The reason it irritates me that HIS 93 is as smooth as MINE is that mine's been getting my brand of anally retentive care, including synthetic fluids since new, etc. His has twice the miles and casual care. Happily, the real story is that this reveals how truly overbuilt the 80s are.

This guy may be talking about the truck having dry shafts, that give it a weird feeling when stopping and starting, or he may be referring to improperly reassembled front drive plates that did not get grease on them and are wearing slack. Or any of a dozen things. These two I mention are 30 minutes and under $50 to fix. Were it me, I'd ask for him to elaborate. Also, you've not mentioned miles or condition here so tough to judge what slack would come from.

DougM