80 In The Snow - open vs viscous coupling center

[White Stripe]

The Colorado mix of snow melt is pretty nasty. I've seen a fair bit of 80s with rotted windshield frames. A newer 5.7 sequoia would be a lot better they have a lot of airbags in a collision. Keep in mind you loose about 40% power on the Colorado passes. So a 210hp 1fz only makes like 120hp on the passes. A 3fe would be down to like 95hp.

 

[flintknapper]

. Keep in mind you loose about 40% power on the Colorado passes. So a 210hp 1fz only makes like 120hp on the passes. A 3fe would be down to like 95hp.

^^^^

This IS a valid and perhaps overlooked point. Most folks will be at an altitude of 6,000 ft. or less most of the time, but on Mountain Passes (12K ft) you can expect to lose roughly 36% power. 3% per 1,000 ft in elevation above Sea Level.

 

[elbarto]

I appreciate y’all’s opinions…this thread did make me do some thinking and I will revive my Audi and give it purpose as a “winter beast”(winter beater?)
It has been mothballed for a couple years because it was giving me too many headaches and was no longer my daily driver. But I can dump a chunk of money into it to fix its issues, refresh what’s gone bad from sitting, even upgrade some things like the diffs and it wouldnt even hit the cost of entry to a busted-ass 80. Even with the performance-centric modifications the Audi has, it’s a great platform for winter-mode.


One day I will own an 80 series, though

 

[PNWTreeOctopus]

I appreciate y’all’s opinions…this thread did make me do some thinking and I will revive my Audi and give it purpose as a “winter beast”(winter beater?)
It has been mothballed for a couple years because it was giving me too many headaches and was no longer my daily driver. But I can dump a chunk of money into it to fix its issues, refresh what’s gone bad from sitting, even upgrade some things like the diffs and it wouldnt even hit the cost of entry to a busted-ass 80. Even with the performance-centric modifications the Audi has, it’s a great platform for winter-mode.


One day I will own an 80 series, though

View attachment 2944083

We will be here to support the future you.

 

[Heckraiser]

Nice, lets see a picture of this sleigh

 

[TLC94LS]

Not open an old wound of this thread but... Ive got a VC question. Im rebuilding a 94 80 series. Im doing a GM swap, bought the vehicle not running with a blown motor at 300k. So this was a swap from day 1 for me. This is my first Toyota of any kind, read too man Jack Carr books, got the LC bug. So rebuilding the T-case because it had only about a pint of oil in it, replacing bearings and seals. No idea about VCs good or bad or otherwise. I already had to rebuild the electric lock motor as well. There was no damage to the t-case gears etc. Everything looks good, completely coated in oil varnish, but no damage. My question is.. is there a way to check the condition of the VC before I reassemble? Or do I need to wait to put it together and then try to spin the fwd/rear out put shafts in opposite directions? Just seeing if there is a method before its put back together, even for a quick dry test fit. Thanks. Obviously at this point replacing a bad VC is nearly impossible, costing about 2k$, which I think you get a whole new t-case for that. If its bad, what is the going method on removal options? Thanks!

 

[TLC94LS]

Not open an old wound of this thread but... Ive got a VC question. Im rebuilding a 94 80 series. Im doing a GM swap, bought the vehicle not running with a blown motor at 300k. So this was a swap from day 1 for me. This is my first Toyota of any kind, read too man Jack Carr books, got the LC bug. So rebuilding the T-case because it had only about a pint of oil in it, replacing bearings and seals. No idea about VCs good or bad or otherwise. I already had to rebuild the electric lock motor as well. There was no damage to the t-case gears etc. Everything looks good, completely coated in oil varnish, but no damage. My question is.. is there a way to check the condition of the VC before I reassemble? Or do I need to wait to put it together and then try to spin the fwd/rear out put shafts in opposite directions? Just seeing if there is a method before its put back together, even for a quick dry test fit. Thanks. Obviously at this point replacing a bad VC is nearly impossible, costing about 2k$, which I think you get a whole new t-case for that. If its bad, what is the going method on removal options? Thanks!

 

[SmokingRocks]

I've seen t-cases around for less than 500. Lat one I priced was $350... Perhaps it's just the circles I run in that get me these deals but $2k would prompt me to swap the drivetrain rather than replace.

I don't know if there is a bench test, I guess you can test to see if you can rotate the inner splines separately from the barrel of the unit. If it's locked together it might be an indicator that its seized, otherwise it should spin with some resistance. Viscus Coupling LSD's rely on the fluid being pumped through steering vanes to create a % of lockup, what that means is to actually get a 'soft lock' there needs to be a decent amount of difference in the rotational speed between the front and rear inputs.

 

[kw90surf]

I’ve never driven a viscous coupler 80 in the snow, but I have spent some time in the snow with my open centre diff and have observed this:

With centre diff unlocked, it tracks well in the snow, is smooth and planted, tends to understeer when pushed, and tends to break the front wheels loose first. Drifts awesome with a handbrake initiation.

With centre diff locked it tracks better, is somewhat more planted, neutral when pushed (oversteer possible with effort) and breaks loose (all 4 obviously) less easily.

If I had to guess, I’d say that a viscous case would be somewhere in the middle, and would thus likely perform better in the snow.

That said, my open-centre 80 is an absolute tank in the snow, even with all terrains. I only feel the differences when I’m fooling around purposefully.

 

[Devils Paw 80]

I had a 1997 80 Series with BFG ATs that was fantastic in ice and snow packed roads.

My next 2 Cruisers, 1999 100 Series, with BFG ATs were not nearly as good in the same conditions.

That said, the new owner of my 97 did (have to) remove the VC at 260K miles or so. He didn’t replace it.

Since this was previously missed by me, I will now report that it's the same thing a coworker of mine reported.

She lived on a steep hill, steep driveway in an area of town with more snow and ice than most. Her experience indicated that their FZJ80 was superior in snow and ice to the 2000 UZJ100 they also owned, so the 80 became their winter beater.

 

[Zjohnsonua]

My question is.. is there a way to check the condition of the VC before I reassemble? Or do I need to wait to put it together and then try to spin the fwd/rear out put shafts in opposite directions? Just seeing if there is a method before its put back together, even for a quick dry test fit. Thanks. Obviously at this point replacing a bad VC is nearly impossible, costing about 2k$, which I think you get a whole new t-case for that. If its bad, what is the going method on removal options? Thanks!

Can it be tested out of the vehicle. Yes, but it's difficult. The VC transmits a good bit of torque, so you need a lot to see it work. Easiest way is in the truck, then jack up one wheel and see if you can turn it.

Short of that, you could jam an output flange in it, get crafty with retaining the housing, and see if you can get the output to turn. You'll need some leverage.

 

[SaturnAscends]

Since this was previously missed by me, I will now report that it's the same thing a coworker of mine reported.

She lived on a steep hill, steep driveway in an area of town with more snow and ice than most. Her experience indicated that their FZJ80 was superior in snow and ice to the 2000 UZJ100 they also owned, so the 80 became their winter beater.

Interesting, I wonder why this is. You’d think the 100 might be better with ATRAC and VSC. Although I don’t think the 98-99s had those features.

I have heard the early ATRAC systems could freak out in snow and possibly even overload the front R&P, so maybe that was a factor on the 2000 you mentioned.