I have a 99 and I've had it since 06. I've spent a looooot of time and money trying to take care of it and keep it runinng well.
So as upgrades continue, wheeling continues,

If you have added frame stiffeners:
Was it worth it,
would you do it again,
any regrets,
Has anything cracked, weakened, or become stressed from this?


Thanks all

 

I plated my frame for two reasons. To stiffen it, although I really never had problems with twisting with my soft suspension. The second and more pressing reason was so I could weld my long arm suspension to it instead of just bolting it. That gave me lots of peace of mind

 

Thin uniframes aren't designed to withstand the leverage forces they're put through with offroading and heavy armor and tires. If you want to keep it for a long time then you'll want to stiffen it. Plus it gives it a good base to weld on to like 4.3L XJ said.

 

If the body is hardened steel I'm trying to see if this has become counter productive for anyone?

 

Hardened steel?

 

????

 

Totally worth
Would do again
Zero regrets
No.

That said...if you wheel alot, add stiffeners. If you want to run a cage, it's a must.
You need a proper place to tie in for a cage, the uniframe is not up to that task.
That, and after installing stiffies, ride is much quieter and feels solid. It's not for everyone, but if you're taking it next level, it's a must in my opinion. By next level I'm talking long arms, larger lift, OTK steering and the like...

 

The hardened steel is a heat treated process. When this is heated and cooled again, such as in welding, this can make the metal brittle and crack. If this is the case for xj, idk. Roninofako could likely speak to this far better, but that's what I'm getting at TRCM.

33 now soon 35s and LA..... usual junk.

 

The only "hardening" process I am familiar with is a process developed in the 70s at Wah Chang in Millersburg, OR. It involves mixing a rare earth element in steel at the rate of one ounce to the ton. It allows you to strengthen the steel by about 20% IIRC and used in many unibody cars. That means they can cut the amount of steel and weight by that much. But it doesn't affect welding

 

That is a very very good bit of information that I don't believe anybody ever writes about. Thank you for adding that here!

 

How do you think Jeep got away with the thin metal in our XJs and have it hold up so well? Another tid bit that came from that facility is the titanium nitride (gold) color coating on drill bits. Originally it was developed for carbide lathe bits so they would last about three times as long when making railroad car wheels, which are made out of fairly hard metal.

 

I know what hardened steel is, and I know of none on our jeep chassis or bodies. It may be stronger than mild steel, but not hardened. It may be an alloy for the stronger metal thus less needed weight wise, but not hardened.

Welding is a different thing......that is not hardening, it is called the heat affected zone. It does harden the metal and make it brittle, but it is not the same process as there is no quenching or tempering, and little if any, temperature control is involved.

Just because the metal got hot and got hard and brittle in a certain area does not mean it has been hardened. This one reason they use spot welds vice stitch welding or lengthy weld runs on a vehicle body....the metal is just too thin.


.

 

i personally dont have a comparison but i knew a guy who would buy xjs and wheel them hard for a year or two then dump them as the cracks started to form on the unibody. this was several years ago when xjs were really cheap.