Cuiser 9" vs 8" high pinion strength (1 Viewer)

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Cruiser 9" vs 8" high pinion strength

Can anyone out here comment on the strength of the cruiser 9" diff vs the 8 inch high pinion diff in the forward drive front axle application.. The 9" is driven on the coast side of the tooth, whereas the high pinion is driven on the drive side.. Does the difference in tooth drive side make up for the difference in ring gear size?

Just another crazy idea of mine.. I got thinking that I could use a mini axle with a sleeve on the short side and run a 40/60 short side inner axle shaft to get 60 axle width in the front for my SOA axles. High pinion would improve driveline angles. Is it worth it? I do like doing things the hard way..
 
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While a very nice diff, I consider the 9 the best diff you can do, it's a 2000 dollar third and he's asking about factory Toyota style solutions...
 
well toyota had your exact thinking when they put an 8" HP in the front of the FJ80's, and they tend to blow up while backing up. i just dont understood the logic of spending alot of time and money for a downgrade in strenght.

if your having issues with driveline angles, your rig is too tall!

Use an FJ60 axle, or widen it if you need to!

and yes, Mega Hi 9's are the Bees Knees. originaly when i read the thread titile, i thought it said Currie 9" vs 8"
 
I just thought I could build something with the junk I have laying around on the shed floor.. I understand the advantages of the 9" in reverse, but I was more interested in forward performance.. Not interested in messing with Hi9s..
 
The Toyota high pinion 8" works just fine in the front of those heavy pig 80 series, I cannot see why it would be junk in the front of a 40.

:meh:
 
I'm SOA w/ the 8" mini truck front axle, 30 spline longfield super set axles, axle truss for extra strength, a lockrite locker disc brakes (will eventually get upgraded to the vented rotors), crossover histeer, etc... I think its a good setup on my 40 w 37's... I'm looking at 4 linking the rear and swapping out my welded rear diff to something selectable to make things more road friendly... You will have to put perches off the frame to outboard the leaf springs in the front... Several people make kits for this...
 
I run a hipinion elocker and have had no issues.

I used to get about 6 months out of the old gears with 5.29s. I went back to 4.10s and went to a hipinion and havent had a diff problem since.
 
The Toyota high pinion 8" works just fine in the front of those heavy pig 80 series, I cannot see why it would be junk in the front of a 40.

:meh:


I have seen the 8 grenade twice, second time the gears were cold treated for more stength...:popcorn:

Driving style of owner was more stupid than anything, pinched between two trees with doubler case and getting on the skinny pedal...

Basically, I said to the guys standing beside me, its going to rip off some ring teeth off and blammo....
 
The Toyota high pinion 8" works just fine in the front of those heavy pig 80 series, I cannot see why it would be junk in the front of a 40.

:meh:


I have seen the 8 grenade twice, second time the gears were cold treated for more stength...:popcorn:

Driving style of owner was more stupid than anything, pinched between two trees with doubler case and getting on the skinny pedal...



Basically, I said to the guys standing beside me, its going to rip off some ring teeth off and blammo....
 
I have a mate with a locked 80 series, blown the front twice, both when reversing on 35's. Myself and a mate have low pinion fronts, bead locked with diff locks. Done lots of stupid stuff, airborne landings while on the governer, rocks and silly stuff at times and have not had a problem driving on the coast side of the diff.

I do not know why it is strong on the coast side where as the 8'' is weak on the coast side. Side my side the 9'' is alot larger, could be stiffer housings on the 9'' helping to hold it together along with its physical beef.

What are you trying to do? If you need hi pinion and can live with 4.1 gears stick a patrol hi pinion diff into the cruiser housing. Hi pinion and a ~9'' ring gear and proven very strong.
 
I have seen the 8 grenade twice, second time the gears were cold treated for more stength...:popcorn:

Driving style of owner was more stupid than anything, pinched between two trees with doubler case and getting on the skinny pedal...



Basically, I said to the guys standing beside me, its going to rip off some ring teeth off and blammo....




Bind up anything and watch it fail... :clap:


:meh:
 
Bind up anything and watch it fail... :clap:


:meh:





There is a video on Pirates of Belly Dock climbing a ledge, not so tought looking...:doh: then you hear the 1 ton rear axle snap and I think it was a chromo......
 
the open 8 " has a piss poor design, period. not a lot of meat in there.
the factory electric locked 8" is one tough beast
but
as already stated
an agressive driver can break anything.
 
There is a video on Pirates of Belly Dock climbing a ledge, not so tought looking...:doh: then you hear the 1 ton rear axle snap and I think it was a chromo......

This is wrong. He was wheeling with me. He has not broke a rear 1 ton shaft. He broke a front shaft but there is no video.
 
YouTube - The hills have eyes trail in Apple Valley Part 2
1:00 minute

Its a 14 bolt if I remember correctly... However he didn't damage the ring and pinion just destroyed a shaft, by comparison to an hp 8" its much cheaper...

I wouldn't run the 8" stuff anymore, not that its terribly bad, its just not strong enough. That is to say you will break some pinion teeth given enough time/ hard enough wheeling. In my experience with Longs you will either blow the hub or take teeth off the pinion.

In a light buggy (ftoy) they seem to live just fine, however a clapped out 22re doesn't have very much torque. That being said I have broke a few with a clapped out 22re...
 
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Boing,

You are right, the axle in that video was a 14 bolt, but I think that you were being corrected that it wasn't Belly Doc.

Belly Doc just posted that video as an example of how much twist there is in an axle before it goes. If you watch one wheel spins quite a bit while the other is stationary. Doc did break a front axle and it was a Chromo shaft.

You can break anything, if the circumstances are right and you are willing to beat your junk.

Ryan


YouTube - The hills have eyes trail in Apple Valley Part 2
1:00 minute

Its a 14 bolt if I remember correctly... However he didn't damage the ring and pinion just destroyed a shaft, by comparison to an hp 8" its much cheaper...

I wouldn't run the 8" stuff anymore, not that its terribly bad, its just not strong enough. That is to say you will break some pinion teeth given enough time/ hard enough wheeling. In my experience with Longs you will either blow the hub or take teeth off the pinion.

In a light buggy (ftoy) they seem to live just fine, however a clapped out 22re doesn't have very much torque. That being said I have broke a few with a clapped out 22re...
 
That was a ford 9" axle not a 14 bolt.
 

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