A while back i was debating on doing a diesel swap. Well my 100k 4.0 threw a rod at the moon, so im cannibalizing all of my parts, and building my jeep from the ground up. The plan is cummins r2.8 diesel engine, tr4050 5 speed, atlas tcase, rebuilt front and rear axles from my 97' f350 parts truck, 4 link suspension with coilovers, roughly 5.5in lift, 35"-37", on board air system, modernized interior, even heated seats. My goal with this jeep is to build it better than the newer JLs. I know its going to cost a lot of money, nothing usually goes right. Im still in the process of stripping parts to prepare the frame and tub for sandblasting, so im open for all suggestions, experiences, and concerns. What works better with what? Whats something overlooked that I might not think about?
TJ build discussion
- Thread starter Revenant4x4
- Start date
The builds for 35s and 37s is drastically different. And within those builds are a tremendous amount of variation.
Breaking your build down into sections and narrowing down the goals will help with meaningful discussion.
What about the JL do you want your old TJ to be better at doing?
Breaking your build down into sections and narrowing down the goals will help with meaningful discussion.
What about the JL do you want your old TJ to be better at doing?
What wheelbase are you considering for your build?
37s on a TJ without a stretch will result in a crippled rig in terms of performance - since the wheelbase actually gets shorter when you lift a rig, still use stock axle locations and put larger tires - think about this carefully. Without properly adjusting the wheelbase, 37s are entirely pointless. And note that 5" stretch doesn't give you 5" over stock - part of that will be needed to recover what is already lost.
Like @jjvw said, 35s vs 37s require very different things to get them to work properly .. only exception is if you are building for looks first and performance secondary, in which case, none of this will matter.
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Not entirely accurate. Yes, without new control arms, the wheelbase will shorten as the stock arms swing towards each other. The length between the front tires and rear tires will get smaller, but that is not wheelbase; wheelbase is the axle (wheel) center to center.
On such a short vehicle as the TJ, anything over 35’s require a lot of re-engineering the suspension to get an OK ride and handling.
Even with my mid arms, the wheelbase was shorter than stock. Currently, my front axle is pushed forward about 1.75" and the rear is against the gas tank skid at full bump. My wheelbase is not quite an 1" over stock.
My goal for 35s is 101" after moving the rear back another 6".
That is going to be a huge undertaking. I may have missed it but are you planning on doing the work yourself? Do you have all of the equipment to do these mods? What is the intended use?
I would really think this through before I spend another dime or time.
I buy alot of torn apart tjs because people pay 10k for a nice jeep, tear it into a million pieces in the garage and then the old lady gets knocked up and the jeep is the first thing to go.
I then swoop in and buy the whole mess for pennies on the dollar. I would suggest looking through the build forum here and I wish you luck
I would really think this through before I spend another dime or time.
I buy alot of torn apart tjs because people pay 10k for a nice jeep, tear it into a million pieces in the garage and then the old lady gets knocked up and the jeep is the first thing to go.
I then swoop in and buy the whole mess for pennies on the dollar. I would suggest looking through the build forum here and I wish you luck
? Over stock, yet shorter?
Regardless, as @jjvw states, there will be a lot of work to get 35 and up to work properly. Long enough arms to keep stock WB, you’ll start crashing into things that once cleared.
Do a better job at quoting.
"Long enough" arms aren't going to restore the factory wheelbase. Nor should wheelbase be a primary motivating factor for longer arms.
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Do a better job at quoting.
"Long enough" arms aren't going to restore the factory wheelbase. Nor should wheelbase be a primary motivating factor for longer arms.
Don’t listen to Josh. Get the longest arms you can and cut the back of your Jeep off. If the front arms aren’t mounting behind the driver seat they aren’t long enough.
In the spirit of the 4th, “The right of the people to keep and bear (long) Arms, shall not be infringed.”
Hooray for independence and individualism. If it weren't for the assistance from the French way back when, we would be doing it the English way.
You all better hope @Jerry Bransford doesn't pop in here and see these shenanigans
Youre 100% right, i forgot to mention im stretching the wheelbase about 9in total between the front and rear. I want the wheel to look centered in the wheelbase, but I care more about function
Im doing the work myself, the only thing Im not confident with is regearing the axle, but i have the equipement for pretty much everything else. I didnt spend a lot on this jeep, it has more sentimental value than materialistic. Intended use is the most offroad capable daily that still reaches 70mph. Also i need the project to keep my mind busy
I guess the easiest way to put it is i want it to be more offroad capable than the JL, while having most of the features, but with a better diesel engine, and more comfortable manual transmission than the newer jeep manuals. As for 35s vs 37s, I dont see a real need to go past 35, 37in militarys are just easier to find for cheap. With that aspect im just trying to compare practicality vs price of replacement
My thought is that whatever the JL can or can't do better than a TJ is irrelevant since the two vehicles are not very comparable. And they become even less so once they are modified.
And once you start building for a tire size, the cost you dump into the rig to get there will far outweigh whatever a set of tires cost. Even on an a solid short arm build for 35s.
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