Front Diff and T-Case Carnage (1 Viewer)

[dclee]

The 105 has it's share of front diff breakages too... though likely not as frequent.

One thing about the 105s (and 80s) is that, while they don't break as much going forward, they are pretty darn fragile in reverse. No, they don't use a Hilux diff, but they do have that reverse cut high pinion. That's mainly so that they can get lots of strength when the gears are turning the truck forwards for the cost of smaller components and lighter weight, but they pay for it when you snick it into "R." I believe the 100 is also reverse cut in front, but they seem to be be breaking in BOTH directions!

Give me a Nissan Patrol front axle any day! Or something with portals to take some of that torque load off the diff. Like a Unimog!

Err...

 

[NeilC]

One of the issues that I believe might cause front diff breakage and this is pure speculation. Toyota designed ATRAC to work smoothly(relative to full throttle, tire hitting the ground spinning) at less than full throttle. If you go high throttle or full throttle with one front wheel off the ground ATRAC shuts off and allows the tire to spin uncontrolled. Once the tire regains traction abruptly with a 33 inch tire on a 5000 lb plus vehicle, the diff is going to break. This not unique to Toyotas it is just the shock load is too high. When people mod offroad vehicles, they all want bigger stronger axles and stronger lockers. I don't blame Toyota. If you were to ask the engineers that designed the front diff, "Why does the thing break when you have one front wheel off the ground or atleast in a no traction situation and you give it full throttle as the tire abruptly regains traction?" They will reply, "Why would you do that? You are over powering the ATRAC." They would probably call it driver abuse. I will wheel mine but will be careful to not overpower the ATRAC until I have a front locker. Just my 2 cents.

 

[Real]

Seems to make sense. So, here's a question from someone who has never owned a rig with lockers.

What is it specifically about installing lockers that improves the strength of the differential?

Is it stronger Ring and Pinion gears, since it seems like that's the weakest link?

Is it the fact that the locker will not allow a wheel to spin freely only to be stopped abruptly when traction is regained?

Or is it something else?

 

[lowtideride]

Exactly. If you want to be VERY prepared then buy 2 hub flanges and machine the splines out...it'll keep dust/grit from contaminating the bearings. Drop the front drive shaft and you're good for $1,800.00 .

Why thank you.

 

[sleeoffroad]

Seems to make sense. So, here's a question from someone who has never owned a rig with lockers.

What is it specifically about installing lockers that improves the strength of the differential?

Is it stronger Ring and Pinion gears, since it seems like that's the weakest link?

Is it the fact that the locker will not allow a wheel to spin freely only to be stopped abruptly when traction is regained?

Or is it something else?

It is both, we have seen broken spider gears and in that case the internals of the ARB is 300M metal and is stronger than the stock internals.

However I believe most of the breakages happen due to shock loads, so when the locker is locker, you avoid the 1 wheel spinning scenario. However if you then spin both wheels and one suddenly grab traction you will probably break the ring and pinion and not the internal spider gears.

 

[NeilC]

I want to tell you that almost all of the trucks/suvs that are 1/2 ton and below are subject to breakage in the situation where one wheel is spinning fast and all of a sudden grabs traction. Jeeps are the same way. That is why they upgraded the Rubicon to Dana 44s front and back. Bear in mind that the jeep is way lighter and has a lot less torque. People with 44s want to upgrade to 60s and so on. Does anyone know if the new Tundra front diff is bigger than the LC but is still similar enough to install into a LC?

 

[Letsgomoreplaces]

strength

Well add me to the list of broken front gears. It happened on a trail run with my 100 and 3 trailered rigs. I am pretty sure it happened on a steep rocky climb, where the tires came up and back down and grabbed. This was with the arb locker engaged. It did last me about 60000 miles of daily driving, several offroad trips, and regularly towing a 5500 lb boat.

There are not many things you can do to strengthen the diffs. As christo was saying the ARB is much stronger, and the case will not deflect as much. Most breakage occurs due to shock-load that causes enough deflection to bread teeth. It is important that you have quite a bit of carrier bearing preload, this prevents the bearings from spinning in the housing, as well as prevents deflection.

The 80 and 100 use the same front ring & pinion, but the solid axle design will generally be stronger. Another week point of the 100 diff is the 3rd member housing is relatively thin and prone to flex, there is not much/any gusseting, I think this is a big factor.

With an arb, extra carrier bearing preload, solid pinion preload spacer, it is about as strong as you can get it, but not necessarilly strong enough for everyone.

Seems to make sense. So, here's a question from someone who has never owned a rig with lockers.

What is it specifically about installing lockers that improves the strength of the differential?

Is it stronger Ring and Pinion gears, since it seems like that's the weakest link?

Is it the fact that the locker will not allow a wheel to spin freely only to be stopped abruptly when traction is regained?

Or is it something else?

 

[hks3sgte]

Is the front diff "carnage" a U.S. documented thing only? Or is it an international thing on IFS 100s also?

 

[gearguywb]

LIke no kidding; heck, those pieces of tin are tearing themselves apart.
g

being a little harsh aren't you?

 

[spressomon]

Well add me to the list of broken front gears. It happened on a trail run with my 100 and 3 trailered rigs. I am pretty sure it happened on a steep rocky climb, where the tires came up and back down and grabbed. This was with the arb locker engaged. It did last me about 60000 miles of daily driving, several offroad trips, and regularly towing a 5500 lb boat.

There are not many things you can do to strengthen the diffs. As christo was saying the ARB is much stronger, and the case will not deflect as much. Most breakage occurs due to shock-load that causes enough deflection to bread teeth. It is important that you have quite a bit of carrier bearing preload, this prevents the bearings from spinning in the housing, as well as prevents deflection.

The 80 and 100 use the same front ring & pinion, but the solid axle design will generally be stronger. Another week point of the 100 diff is the 3rd member housing is relatively thin and prone to flex, there is not much/any gusseting, I think this is a big factor.

With an arb, extra carrier bearing preload, solid pinion preload spacer, it is about as strong as you can get it, but not necessarilly strong enough for everyone.

You are the first AFAIK that has broken the front diff with the ARB front locker mod. Did you shear the R&P? Darren insists, to further strengthen the 100 front diff, to check and machine the ARB carrier...sorry can't remember what he states the run-out should be...but according to him very few if any ARB's are good out of the box...

 

[Letsgomoreplaces]

ifs

There was no run-out on the setup, not that this has anything to do with strength of a ring & pinion. I actually didn't even realize it was broken until a couple weeks later as there was no banging or popping. Only half of one R/G tooth broke off and was sitting in the bottom

 

[ats4x4dotcom]

You are the first AFAIK that has broken the front diff with the ARB front locker mod. Did you shear the R&P? Darren insists, to further strengthen the 100 front diff, to check and machine the ARB carrier...sorry can't remember what he states the run-out should be...but according to him very few if any ARB's are good out of the box...

You "MUST" check the arb carrier for run out, they are allot better these days, have seen up to 54 thou runout, these days a bad one has 12-15 thou, [arb spec is < 7 thou] and you cant get a good pattern with that...... just due dillagance on doing a good job as it goes together, just like the oil up the air line problem, its caused by improper install, not a locker fault these days, and we have only ever had one thats done it, but we have fixed many many many........

Also, you "MUST" solid pinion spacer the pinion, and get the pre load right, as well as machine the spacer so it takes on the full face of the bearing with as much contact area as possible, especially the nib section that holds the rollers on track.

We also never ever use the bearings again, even on a brand new car, always replace them.

And on a 105 [same as 80] we drill out the carrier and housing and fit rear housing studs [same as rear axle studs on a 105] 10mm, and nuts and washers, save the oil leak between 3-6 o clock that housing flex from wheeling can create on 80 and 105.

Live axle 105's use the same crown wheel and pinion, well, they fit, different part No's but you can fit live axle ones into IFS carriers, we discovered it when there were no IFS ones in stock, but we had a live axle one, and we thought "hey....looks like a.... live axle one"

Done hundreds, most broken, some more than once [ up to 4 times for some] never had one back after mods broken, had 3 with broken cv joints, none with broken diff again, after we mod it.

I know what I put my front 80 diff through with 36" swampers and 400 hp at the wheels after i broke the first one in 96, when i came up with the mods, and treating it with respect in reverse, I found it bullet proof.

Used to be a vid on christo's website of what it used to put up with, [found it] Video of daz 98 - Photobucket - Video and Image Hosting also found this vid of a mates 100 and how to break a standard ifs 100 diff, in a truck weighing aprox 9000lb on a remote trip..... Video of ivan boom - Photobucket - Video and Image Hosting plus Stormin Norman vid was my 80 truck just after I sold it, still with diff mods at woodpecker, if you have seen it. MySpaceTV Videos: Stormin Norman by -=TallPaul=-

 

[CrusrDug]

That last one is someone definitely having some fun!

 

[farinvail]

I wheeled mine pretty hard for 3 years before I broke the bront dif. Your "average" driver has nothing to worry about. If you've ever thought to yourself,"It'd be nice to have a roll cage in here," your gonna break something eventually. If you've never broken anything on your truck, you're not driving where we're driving any don't even worry about it. Good idea to learn how to remove the drive plates in the driveway instead of on the trail and front driveshaft. A 100 will rally in 2wd no problem.