best year for the 100 series?? (1 Viewer)

[Cruiserdrew]

The place that Snook took out his front diff (4 pinion) did not look much worse than that either. It's just a weak design in my opinion. I would like to hear more about how it happened from Shotts. ie, was he spinning and then locked up (like Snook) or was the failure mode different.

 

[Liam]

After seeing a '99 destroy a front diff at a moderate obstacle 2 weeks ago I'd never take one on the dirt until it had an ARB or a 2000+ 4-pin swap-out. Look at the obstacle. A 2000 with TRAC would have clawed right up.

how hard is it to swap to a 2000+ 4-pin?

 

[Jim_Chow]

FWIW, if any of you have been following the FJC threads, they've had a problem with the rear locked diffs blowing apart when one wheel is spinning and suddenly gains traction. Ditto w/ the locked Prado Down Under. Apparently, the Prado platform only uses a 8" rear diff (the same size the mini's used) while the weigth of the vehicle has dramatically increased over the years (~ 4200 lb).

 

[cruiser4life]

After seeing a '99 destroy a front diff at a moderate obstacle 2 weeks ago I'd never take one on the dirt until it had an ARB or a 2000+ 4-pin swap-out. Look at the obstacle. A 2000 with TRAC would have clawed right up.

I think we all agree that the 2 pinion front diff is less preferable than the 4 pinion but...

It seems that these failures are really random - situation, environment, obstacle(s), etc. The in-the-air wheel spinning and then coming down on something immovable seems to be key but what else? Towing / snatching in reverse I think has eaten a few.

For instance, I just had my 98 100 series at Tellico and while I didn't do anything insane, I did 4,5 and 6 and had zero issues. On a rainy day like we had, pulling cable and using snatch straps on rigs is typical. I know I might be gambling a bit but some of the obstacles we traversed were MUCH more menacing than this or some of the other stories here about blown diffs in 4 inches of snow or the like.

I've wheeled my 98 in lots of different challenging places since I've had it and it has never let me down. I wouldn't hesitate to take it out and put it through the paces tomorrow either.

All of that being said, it is a known weak point that will probably cause an issue at some point. When, what conditions and where - I don't know...

Meanwhile, my 2000 with the 4 pinion rarely leaves the pavement anymore. Although it has TRAC, it wouldn't "claw right up" that obstacle any easier than my 98.

 

[Snook]

After seeing a '99 destroy a front diff at a moderate obstacle 2 weeks ago I'd never take one on the dirt until it had an ARB or a 2000+ 4-pin swap-out. Look at the obstacle. A 2000 with TRAC would have clawed right up.

Sheesh, I thought I first thought this is a photo of me w/ brown hat packing spindle hubs in a plastic at Slick Rock Trail!

With Andy's suggestion, I grinded out the spare spindle hubs so there is no 32 spindle inside. That way in the future (heaven forbidden) I can use it to sealed up for dust and water protection while spinning free.

Alvaro brought up a good question, he want to know if this is compatible with 80's?

Cheers,

 

[ShottsUZJ100]

Although it has TRAC, it wouldn't "claw right up" that obstacle any easier than my 98.

My 2001 would have easily climbed this ledge with TRAC alone. It was a "nothing obstacle". Rear-lock only didn't help. Rear wheel traction was slight here. He needed help from the front and didn't get it on '99. TRAC would have given him that help.

And yes....what obstacle? While "jerking" to get up the ledge it just SNAPPED! This was only his 3rd or 4th time out.

 

[ShottsUZJ100]

My 2001 would have easily climbed this ledge with TRAC alone. It was a "nothing obstacle". Rear-lock only didn't help. Rear wheel traction was slight here. He needed help from the front and didn't get it on '99. TRAC would have given him that help.

And yes....what obstacle? While "jerking" to get up the ledge it just SNAPPED! This was only his 3rd or 4th time out.

If you look at the pic again you'll see the rear wheels were in wet and slippery mud. The fronts were not. This is just another example of why I've always said a TRAC-controlled 100 can OVERALL easily out-wheel a rear-lock only 98-99.

 

[Snook]

If you look at the pic again you'll see the rear wheels were in wet and slippery mud. The fronts were not. This is just another example of why I've always said a TRAC-controlled 100 can OVERALL easily out-wheel a rear-lock only 98-99.

Did he enabled his center locker?

I forgot to enabled my center locker so all of the 100% (instead of 50% or so) energy went into any free slipping wheel, that happens to be up front then this wheel suddenly stopped as it gained traction and the remaining energy has no place to go but the weakest link, the front axle itself. Yes, there was a wet spot in my rear at that time.

Regards,

 

[cruiser99]

As I am re-gearing, I am looking at the front diff (gears and all, 99 model) and it looks brand new. I start thinking that the problem with the diff is a manufacturing problem. My truck sees lots of ard work on a regular basis.

IMHO

 

[ShottsUZJ100]

Did he enabled his center locker?

I forgot to enabled my center locker so all of the 100% (instead of 50% or so) energy went into any free slipping wheel, that happens to be up front then this wheel suddenly stopped as it gained traction and the remaining energy has no place to go but the weakest link, the front axle itself. Yes, there was a wet spot in my rear at that time.

Regards,

Center and rear were locked. The rear had little traction...wet/muddy. My point is for this potential owner to buy into the merits of 2000+ and TRAC. The small price difference gains large rewards IMO.

 

[dclee]

Did he enabled his center locker?

I forgot to enabled my center locker so all of the 100% (instead of 50% or so) energy went into any free slipping wheel, that happens to be up front then this wheel suddenly stopped as it gained traction and the remaining energy has no place to go but the weakest link, the front axle itself. Yes, there was a wet spot in my rear at that time.

Regards,

Oh man that is ugly!

 

[sleeoffroad]

I don't think it is a 2 pinion vs 4 pinion deal. I broke a front ring and pinion exactly like that with a ARB in the front. I believe it is a front wheel spinning and then grabbing traction deal. The resulting shockload breaks the gears on the R&P. I also broke a front R&P on a 80 series front end in the same manner.

 

[cruiser4life]

That makes sense. Much more logical than a 98/99 vs 2000 (w/TRAC) comparison to me.

 

[SINCITY100]

Center and rear were locked. The rear had little traction...wet/muddy. My point is for this potential owner to buy into the merits of 2000+ and TRAC. The small price difference gains large rewards IMO.

Good lord... !!

After seeing and hearing more and more stories about blown front diffs, I cant believe that mine hasnt given out a long time ago I swear I have relentlesly abused my front end time and time again, spinning and grabbing at full throttle on mixed-traction surfaces.. without ANY issues... It sounds almost as if it (failure) is as, or perhaps even less, random than any other "failure" on a 100.

I am sure that the front diff is the weakest link, but I still have a lot of faith in my 4 pinion.

OK.. I probably just jinxed myself...

ANY bets on when my front end explodes ?

 

[Jim_Chow]

If you look at the pic again you'll see the rear wheels were in wet and slippery mud. The fronts were not. This is just another example of why I've always said a TRAC-controlled 100 can OVERALL easily out-wheel a rear-lock only 98-99.

So this is how I understand it: the shock from a free-spinning wheel suddenly gaining traction blows the ring gear. The TRAC-equipped vehicle would likely not have blown its diff since the wheels probably would not have been free-spinning in the first place?

 

[Snook]

So this is how I understand it: the shock from a free-spinning wheel suddenly gaining traction blows the ring gear. The TRAC-equipped vehicle would likely not have blown its diff since the wheels probably would not have been free-spinning in the first place?

Yes in theory, but somehow in a real world, my ring gears did failed while I am in A-Trac mode. (Mine is 2000) I did put a bit much gas assuming my center locker was engaged but it wasn't.

One other thing, I did noticed is that once I let go of the gas pedal, there is still ongoing momentium for one seconds before the wheels actually stop.

Regards,

 

[Liam]

Center and rear were locked. The rear had little traction...wet/muddy. My point is for this potential owner to buy into the merits of 2000+ and TRAC. The small price difference gains large rewards IMO.

does trac out weigh quality issues?? Can i put a ARB locker in and this question of TRAC vs. Locker be a moot point??

As far as i can tell and have heard - 98/99 100's seem to be more reliable

 

[sleeoffroad]

One other thing is that the 4.7 is such a quiet motor that it is easy to rev it to redline and not even knowing if you are not looking at the tac.

PS, when I blew up the front, the ARB was not locked. I also broke the front axle shaft at the same time. I firmly believe the shockload is what breaks the gears. We see it in heavy rock crawling with other trucks a lot. lAxle snaps, bang goes the ring gear due to the shockload on the gearset.

 

[ShottsUZJ100]

That makes sense. Much more logical than a 98/99 vs 2000 (w/TRAC) comparison to me.

Ummm.......let's think about this another way:

Of all the cases we've heard about front diff and R&P failures in 98-99:

Some had front diff failure only. (Like my recent friend)

Some also had R&P failures along with the diff failure.

So, while some had R&P failures...ALL who failed had wrecked diffs though not all had wrecked R&P. Follow?

I think the diff is the weak point and when it goes it SOMETIMES takes out the R&P. It's not the reverse.....that the R&P goes and the diff gets taken out also.

???

 

[ShottsUZJ100]

So this is how I understand it: the shock from a free-spinning wheel suddenly gaining traction blows the ring gear. The TRAC-equipped vehicle would likely not have blown its diff since the wheels probably would not have been free-spinning in the first place?

Hmmm.....not really. The TRAC rig would have climbed right up the ledge because it offered traction assistance up front. A front-locked rig (no rear lock even) would have done the same.

Rod's rears were just spinning in the slickness. The open front diff gave him almost zero traction also. So yes....he did bounce some here and there though not enough so to mangle a diff. We were all surprised.

I guarantee you a 2000+ would have approached the ledge...climbed the front wheels on top of the ledge, then crawled it's way right up be shifting that power around....mainly on the front. This was not a bad obstacle...just bad for a rear-lock-only vehicle.

If the rocks were not wet and slick then Rod would have climbed right up. There's just too many scenarios where TRAC slaps a rear-locked rig in the boonies.