Ooo...bugga.

petefj40 · Post by **petefj40** » Thu May 03, 2007 7:06 am

I'm wondering what's a stronger diff head than what I already had in the rear of my 84 FJ40. Yesterday I sheared the pinion shaft while doing a burnout. (bugga) God knows how I gotta away with doing so many before now. But looking at the break there is some dirty looking steel in there so it may have been cracked before the extra 400 horses went in. Has anyone gone for a stronger diff head? Cheers for any feed back! Pete

Aaron · Post by **Aaron** » Thu May 03, 2007 9:30 am

I have also broken a pinion a while back, its not the strength its the movement of the rear axle thats the problem.

If you made up a brace to stop the diff head moving up and down you wouldnt have any more problems. :wink:

http://forum.ih8mud.com/showthread.php?t=75246&highlight=ladder+bar

petefj40 · Post by **petefj40** » Thu May 03, 2007 9:35 am

Aaron wrote:I have also broken a pinion a while back, its not the strength its the movement of the rear axle thats the problem.

If you made up a brace to stop the diff head moving up and down you wouldnt have any more problems.
http://forum.ih8mud.com/showthread.php?t=75246&highlight=ladder+bar

I see! I think I might look into that. Cause I can see it happening again if I don't do something. Cheers! :salut:

Jungle · Post by **Jungle** » Thu May 03, 2007 3:17 pm

Please add pics.

Burnouts in old 40 series trucks will always turn heads.

G

petefj40 · Post by **petefj40** » Thu May 03, 2007 3:38 pm

Jungle wrote:Please add pics.

Burnouts in old 40 series trucks will always turn heads.

G

Agreed, but not if I keep breaking things. :scratch:
I need a setup to stop the diff twisting under max load. Hmmm

wopass · Post by **wopass** » Thu May 03, 2007 7:41 pm

you really need to get video/photos of your fun mate :twisted:

thats gotts sound cool :wink:

and as for the pinion,yea ive smashed a few of them then i did this
rear

front

very simple and so far pretty effective. will see if it can handle the berrys with the chev in the hole

wopass · Post by **wopass** » Thu May 03, 2007 7:43 pm

and how the front brace is mounted to the chassis

petefj40 · Post by **petefj40** » Thu May 03, 2007 8:18 pm

Cheers mate! Hey great pictures. That looks like the way around it. Impressive!
Yeah I should get some vids done of the fun we have in the fj40. It's a laugh doing big smokey burnouts in it. It's easiest when I have the tandem axled trailer loaded up on the back. Holds the back down nicely. lol

sig · Post by **sig** » Thu May 03, 2007 8:39 pm

hi little hint try and keep your torque arm the same length as your drive shaft ,cheers sig

petefj40 · Post by **petefj40** » Thu May 03, 2007 8:46 pm

sig wrote:hi little hint try and keep your torque arm the same length as your drive shaft ,cheers sig

Cheers!

MNC · Post by **MNC** » Thu May 03, 2007 9:23 pm

Aaron wrote:I have also broken a pinion a while back, its not the strength its the movement of the rear axle thats the problem.

If you made up a brace to stop the diff head moving up and down you wouldnt have any more problems.
http://forum.ih8mud.com/showthread.php?t=75246&highlight=ladder+bar

OHHHH! Thats why I broke the pinion!

I couldn't believe that I managed to snap a piece of metal soo thick. I wasn't even SOA at the time - just pressure of locker (and a bit of bounce :oops:

sig · Post by **sig** » Thu May 03, 2007 10:24 pm

you dont get a hell of a lot stronger diff head than cruiser ,sure ford nine inch are pretty substantial but cruisers have superior side gears (size wise and steel quality wise) .plus cruiser heads are cheap as .did you have a 2 spider open head or 4 spider lsd .if you are chewing out front diff heads put a lsd in the front with the spring removed this has made my front last a hell of a long time ,dana make some big diffs but they are just that BIG diffs and not cheap or easy to get and maintain

petefj40 · Post by **petefj40** » Fri May 04, 2007 7:32 am

sig wrote:you dont get a hell of a lot stronger diff head than cruiser ,sure ford nine inch are pretty substantial but cruisers have superior side gears (size wise and steel quality wise) .plus cruiser heads are cheap as .did you have a 2 spider open head or 4 spider lsd .if you are chewing out front diff heads put a lsd in the front with the spring removed this has made my front last a hell of a long time ,dana make some big diffs but they are just that BIG diffs and not cheap or easy to get and maintain

Cheers!

tristanp · Post by **tristanp** » Fri May 04, 2007 7:18 pm

i think you will find that it will bend pretty easy, those threads will hold if the load is a pulling load (under tension ) but load it up the other way and it will bend pretty quick. you could take a look at some adjustable panhard rods and see how they use a threaded tube in a tube , or a really long threaded section to stop them bending, you could even make a fixed length bar

* in one photo the diff head looks pointed to the ground (bad), in another it looks to be pointed at the transfer case(ok only if your running a double cardan joint) ?
and nice work using the bow shackle like that

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