Transfer Case Issue with a 95 HDJ80 Manual Lemon Cruiser

[LemonCruiser95]

Hey team,

I have a very weird issue with my truck that only happens after I have been driving it for about 45 minutes. So recently I had the clutch replaced with a HD clutch as my old one finally died. Since then, if I drive my truck for longer than 45mins I lose all gears in High ratio. However, if I turn my centre diff lock on, it will drive again. All gears work in low ratio also. I then changed the clutch master and slave cylinders with brand new ones, and changed all the fluids in the gearbox and transfer case and this still happens.

Before replacing the clutch, I also put a new crown and pinion in the front dif and replaced 1 full axle (the long one) but the short one is still the original.

So basically my question to the community is, why does my truck lose gears like this? and where should I be looking to fix this issue so I can enjoy my truck alot more.

Cheers

 

[Gav missin]

I'd say viscous coupling at a guess. Warming up and slipping. Especially as it moves once centre diff is locked. Strange as they normally seize though.

 

[Gav missin]

I'm guessing its 24v manual from your picture.

 

[Towpack]

Gav missin beat me to it.
+1 on the VC.
Selecting LR locks the diff by default.
If it drives ok in low it's not the clutch.

 

[Shayne]

Must be the viscous Frank suggested I might free up with some enthusiastic reversing .

 

[LemonCruiser95]

I'm guessing its 24v manual from your picture.

yup, just a GX model, i did score it quite cheap but now im paying for all the lack of maintenance done on it

 

[Gav missin]

Nothing wrong with a gx mate. Most have been poorly maintained because they just keep going without. Get on top of the maintenance, and you'll never look back. Awesome trucks.

 

[LemonCruiser95]

Will it affect driveability if i remove the VC? Should I replace it? This actually explains alot as I broke teeth off my front diff awhile back when i did a hairpin turn coming back from somewhere. Seems to have been my problem this whole time by the sounds of it.

Thanks to everyone for the advice

 

[Gav missin]

Yeah you can simply remove the vc. It's a couple hour or so to do. Think its 9 bolts on the rear housing on transfer box. Think its held on the shaft with a circlip or something like. I'm sure its been covered on here somewhere if you have a search.

 

[Ciderman]

Viscous coupling?
What is this witchcraft you speak of?

I have the 93 HJ80 manual, will mine have one?
Apologies, hijacking the thread - but that sounds like the work of satan

 

[Gav missin]

Later transfer boxes have them. Not sure as you could be right on the change year. Just google both images of t/ box s to check which you have.

 

[frank rabbets]

I don't think a seized Vc would cause loss of drive. Symptoms are tyre squealing and tending to steer straight ahead on bends but not loss of gears.

 

[Gav missin]

No but they can also break instead of seize and this has been known to cause loss of drive.

 

[chapel gate]

Here it is top left. Change the output seal while your in there.

 

[Towpack]

Viscous coupling?
What is this witchcraft you speak of?

I have the 93 HJ80 manual, will mine have one?
Apologies, hijacking the thread - but that sounds like the work of satan

I think the VC was introduced in 1995 along with ABS. If your truck doesn't have ABS it won't have a VC. Please correct me if I'm wrong someone.
The xfer box with a VC will also be marked H2AV.

 

[AndycruiserguyLomas]

VC was introduced when they upgraded the brakes and fitted 16" wheels ( and ABS) , probably sometime in 92.

 

[frank rabbets]

Something's bust in the transfer I would think. I've taken mine out (= Broken?) and I still have drive. Be an interesting story when completed. An oil drop might reveal metal swarf.