Toyota FJ Cruiser Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
2007 FJ, 6 in PROCOMP lift, 35" tires, fab 4 front and rear bumpers... gonna take her off road for the first time soon... ( used to own a wrangler rock crawler, and I got pretty extreme, so I know not to get 'er bouncing, and to take it slow )... and Im wondering, what is the FJ's weak link? Once I start tweaking that suspension and climbing over obstacles, what is going to be my most likely breakage? Id appreciate anyones list of what broke, and in what order, and under what circumstances... Id prefer to just beef it up before I even break it... its more fun to drive home than get towed.
 

·
Registered
Joined
·
838 Posts
07 rear diffs are suppose to be weak
 

·
Registered
Joined
·
111 Posts
The LCA's in the rear aren't that beefy and will bend. All-Pro and some others make replacements as well as skids for the links. That's what I'm worried about going first but I don't have a lift.
 

·
Registered
Joined
·
5,027 Posts
I think steering will be your weakest link on 35"s. I lost a power steering pump with essentially 33"s.

I think that was more of a freak thing. I'm worried about tie rod ends with heavier tires. They just feel weak to me. When I have to replace one, in going to all pro hd ends.
 

·
Registered
Joined
·
1,570 Posts
hey Hub.. welcome to the forum. so far I think I have been real lucky with my setup basically the same pro comp 6 but with Icon's front and rear and stock bumpers still :(. but anyway..

so far I have only knocked the front diff on a fallen tree with stripped out the pinion mount letting the front diff rotate inside of the drop bracket.. nothing major destroyed and was able to repair it. so just take it ez on lining up on obstacles that may contact the front diff it might be pretty well protected but it does still hang down a touch beneath the drop bracket.

and 2x on the rear lower control arms they are very weak. With the 2.5" piggy backs on the amount of droop I was getting caused the rear axle housing to come into contact with the rear lca's Stan hooked me up with a custom set.. when you are out wheeling if you get a rear tire off the ground and are able to safely get out and check it out you might already be having issues there.. read about it here ---> http://www.fjcruiserforums.com/forums/toy-outfitters/106903-lcas-contact-axle-tube-6-lift.html

but so far so good on everything else
 

·
Premium Member
Joined
·
7,676 Posts
Your fabfour bumper will fall off, THEN you'll bust your rear diff :cheers:
 

·
Premium Member
Joined
·
3,185 Posts
You're driving an IFS 4x4. The front diff is fixed in place and the shafts that go to the wheels are double jointed CV axles. There's a tulip joint against the diff, and a birfield joint just inside the hub. The weak link is the ring inside the birfield. Faced with the torsional resistance of 35" tires bound up on rocks, you can break the joint when the steering is close to full lock and the suspension is close to fully drooped on that side.

Unfortunately, I can't tell you that there are part upgrades that are significantly different than stock for this CV axle. There may be, but I stopped following the specifics some time ago. My suggestion is to just carry a spare and be ready to swap a broken one out.

One of the issues that you may encounter if you bust a CV axle is trying to get by in 2WD. Without a front locker, you're not going to be in 3WD.

The rear ring gear may or may not be an issue. There was some concern about early FJC's having a bad batch of gears. I heard allegations of substandard heat treatment done in Mexico... but I can't confirm.
 
1 - 11 of 11 Posts
Top