XJ/MJ weights and dieting

I weighed my MJ today. When I weighed it I had no tools, spares, or people in it and it came to 3600 pounds. I was really thinking/hoping it was around 3200-3300. I'm guessing that with me in it and all the tools, spares, and camping stuff for a weekend on the Rubicon it would be about 4000.

Anyways, I want to get it as light as possible, so what do other people's XJs and MJs weigh? let's talk about some dieting tips.


-axles- I can't think of any reasonable way to loose weight off the axles. Waggy D44 front with crossover, a beefy tie-rod, ARB, hydro-assist. Toyota rear (pretty light).

-tires/wheels- 35" MTRs are what I have and are reasonably light, and not worth changing in my mind for anything lighter. I have 15x10 steel wheels, I plan on getting 15x8s (mostly for reasons other than weight) but aluminums would be too expensive, especially since I would need spacers. Besides, good aluminum wheels weigh almost as much as steelies.

-suspension- I got leafs all around, I don't think there is much to lose there.

-drivetrain- 4.0/AW4/231, again not much to loose without some sort of engine swap. I have an AC compressor, but none of the extra AC stuff, since I have it just for OBA, I'm not willing to give up OBA to save 30-40 pounds

-battery- I have an Optima yellow-top that is relocated low and to the back. this is good for weight distribution, but I doubt it would be worth it to get a lighter battery.

-sheet-metal- Doors is an easy one, I take them off in the summer and probably save 100 pounds there. I already ditched the bed and lost about 120 pounds. I have a bunch of Lexan, and I was thinking of making new fenders and a hood with it. any guesses as to how much that would save?

-protection/skids- my bumpers and skids are probably as minimal as I would want to go.

-interior- I gutted the flooring and have it bedlinered, that probably saved a few pounds. The seats aren't too heavy, but maybe something out of a civic (or similar) would be lighter (and more comfy ). anyone know how much the whole dash assembly weighs?

-tools- this is a big one for me, I really debate on whether I should just carry the basic tools or carry everything just in case. what is everyone's strategy here? how do you find the balance?

-spares- I don't carry any spare shafts or steering. That was a specific goal in my axle swap. I do carry a spare rear driveshaft, since mine is fairly vulnerable with the 115" wheelbase. I carry a 33" spare tire, hopefully I'll be getting a 33x9.50 soon and put it on an aluminum wheel.



what else am I not thinking of?

glass is pretty heavy, i know on hemi darts they came with the option of plexiglass windows that saved weight

-tools and spare parts-

My tools and spare parts changes with the season and how far from home I am going. I have a couple of different tool boxes with different types of tools in them. When away from home I take tons of stuff but some of it stays in base camp with the truck/camper. Don't have all your stuff in one box then you can tailor what you take on the trial based on that particular trail.

^^
glass is heavier than sheet metal.
carpet and rubber weigh a bit.
i seem to remember you have those taken care of.
so, yeah, like he said.

biscuitboy87 said:

^^
glass is heavier than sheet metal.
carpet and rubber weigh a bit.
i seem to remember you have those taken care of.
so, yeah, like he said.

Click to expand...

yeah, the interior flooring is gone, replaced with bedliner.

I forgot to mention glass, since I'm primarily interested in it's summer weight (doors off) the door glass doesn't matter. I need to keep the windsheild because this sees a lot of street time as well. I did think about replacing the rear window with Lexan, does anybody have a good guess as to what a rear window (XJ or MJ) weighs?

Tools-
If I had a tow rig I'm sure I would leave most of my tools in it, but I don't have that choice. I know what you guys mean as far as the tools being dependent on the trail and the distance from home. Do I bring just every wrench I could possibly need on my vehicle, or do I bring all the other stuff in case someone else needs it? that type of thing.

For tools, I always bring what I need to repair my own vehicle. I keep spare parts at camp and any non essential tools not needed on the trail.

AARON

Just for reference, my stock 88 MJ with AC, stick, heavy duty rear bumper, me, stuff behind the seat, a spare,
and a full tank of gas weighed 3600 pounds at the sand and gravel place. I was a little surprised because the I seem to recall the factory claiming 3000 or maybe it was 3200. I'm about 200 of it.

Fred

oh yeah, I forgot to mention that I had about 5 gallons in the tank.

so on yours, (I assume 4.0?)
3600
-200 (you)
-100 (gas)
-100 (spare and misc behind the seat)

that puts it at 3200. with my bed gone and interior reduced I've probably lost about 200 pounds, so 3000. Therefore my axles and tires weigh 600 pounds more than stock axles and tires, that seems a bit high to me. I wonder what I'm missing.

Regarding wheels, most cast aluminum wheels have no significant weight savings over steel, and no real difference in strength. Forged aluminum wheels however are much lighter (maybe 1/2) and also can be stronger than standard steel wheels. Not sure what bolt pattern(s) you have but a lot of the early/mid 90's ford 1/2 tons used a 5 on ? pattern forged wheel. You can normally tell by the finish, much smoother appearance w/ very little tooling marks as w/ cast wheels. These aren't going to save you huge weight, maybe 10-15 lbs a wheel. But it is rotating mass, and also unsprung weight. So power and susp. performance is improved.

i'd like to use nice aluminum wheels, but I like my 2.5" backspacing, meaning I would need spacers with aluminum wheels. I guess there's a chance I could find some stock Chevy or Yota (6 on 5.5) 15x8s for cheap and get some spacers as well...

Yeah, 4.0.
I don't know how much significance I would give to the empty weight, at the sand and gravel place the only important number is the difference between full and empty. Could be off by a 100 pounds or so.

Fred

3600 lbs is pretty good. Assuming you add a winch & cage you'll push it to 3800-3900, still not bad. Your doors are probably good for 150lbs.

If you're serious about losing weight & getting into the tougher trails that warrant it, I'd upgarde that front Waggy 44 to an HP30. Probably good for over 50lbs & you'll gain some much needed clearance too :wave:

Paul

If you're serious about sending your Jeep to Weight Watchers, inflate the tires with helium. Air's too heavy.

Hesco now has an aluiminum head and block for the 4.0.

Something like 115 lbs. lighter.

Seems like you may be obsessing a bit there Brett. If this is just part of the constant improvement-cycle, that's cool. We all do it. But why exactly is 3300 such a great weight? Maybe you just need some lower gears or a stroker 4.0 to help push that led zepplin of yours around?
By the way, my favorite idea for weight savings is dumping the hood and doors before hitting the trail. I'd be hesitant to permanently ditch the hood if you drive the streets a lot, but there's only a few bolts and I'm sure you could fab something lighter for shedding mud/water while on the trail.
Another biggie is switching to a 2.5L, but let's stick with the *sane* ideas.
Jeep on!
--Pete
ComancheClub.com

Some more ideas (besides the Hesco Aluminum ) :

Synthetic winch line and alum. fairlead (vs. roller)...............25 lbs.
'Glass hood..................................................................15 lbs.
Borla header (vs. stock manifold)......................................7 lbs.

You've trimmed away and are pretty light with your hacked body now, I wouldn't worry about it too much. I'd carry some spare axle and driveshafts and steering if you have them because those things can break. I know you are running 35's on a 44/8", but it can still happen especially with stock shafts.
Troy

When I swapped my 32's from my 15x8 AR Baja's to some 15x8 Soft 8 black steelies I was amazed how much heavier they seemed. I didn't weight them but the difference was significant. To bad alloys aren't practical for your application or you could definitly save some weight there.

3900lbs with no tools or even a spare tire. But a d60 and 9", steel beadlocks,38.5sx's(that weight a freakin ton) and after wheeling my leadsled XJ of 5500lbs I'm happy...your MJ's weight sounds good to me

Paul S said:

3600 lbs is pretty good. Assuming you add a winch & cage you'll push it to 3800-3900, still not bad. Your doors are probably good for 150lbs.

If you're serious about losing weight & getting into the tougher trails that warrant it, I'd upgarde that front Waggy 44 to an HP30. Probably good for over 50lbs & you'll gain some much needed clearance too :wave:

Paul

Click to expand...

how much does yours weigh Paul? I know you've been pretty weight focused...

The D44 will have to stay, it's geared, ARBed, steering done, hydro-assist, etc. The only real consideration I had with the front axle was to put a Toy center-section in with my D44 outers (D44 shafts work in Toy side-gears). It's still a thought I'm kicking around to save probably 40 pounds, better clearance, swapable thirds with the rear, ability to run 5.29s... but that might be a little too much Toyota in a Jeep