depends if they are limited trim or laredo ect. The zj 4.0 tho supposedly weighs like 3500 lbs. The V8 is like 3800, the 5.9 is 4300

 

What on the 5.9L would add a quarter-ton over the 5.2L? I would be hugely surprised if there was more than a 50-lb difference between the two.

 

XJ curb weight 2wd = 2,891 lbs - 2,993 lbs
XJ curb weight 4wd = 3,057 lbs - 3,386 lbs


The XJ AW-4 transmission is a four speed with lockup torque converter.

 

XJ curb weight 2wd = 2,891 lbs - 2,993 lbs
XJ curb weight 4wd = 3,057 lbs - 3,386 lbs

The XJ AW-4 transmission is a four speed with lockup torque converter.

For this discussion, let's assume both vehicles are 4x4 equipped. So that figure is about right then.

And would I be wrong in stating that the 42re(A500) behind the 4.0 in the ZJ is also a four speed with a lockup converter? I know for sure that is three in the case, an OD unit on the back, and my TC locks up at about 47 mph.

I at first thought it was something in the driveline, but I really cannot seem to put a finger on what the difference would be. Unless the weight figures for the ZJ are grossly underestimated.

Steve

Steve

 

The transmission the engine is different, the dana 44 axle, the extra wiring in the whole Jeep and buttons leather seats, metal frame rails on the 2 front moving seats, the speaker rack in the back, the full sized spare tire and full sized rim, tow hooks, skid plates, class 4 tow hitch, the bigger diameter exhaust piping.. It all adds up. I just looked it up the 5.2's weigh around 3980 actually, i know for sure the 5.9's weigh a lot more.

Garuntee you all the stuff i mentioned could easily add up to 200 lbs more. I know for a fact the 360 engine alone weighs nearly 50lbs more then a 318

Most of that stuff isn't 5.9 specific though? Full size spare, d44, the extra wiring is 2-3lbs at best, seat rails, skids, hitch, tow hooks, all came on 5.2's? I believe it's heavier, yes, but not by more than 100-200lbs.

 

stronger and heavier transmission, more material on door panels, soundbar, thicker spare tire cover, supposedly stronger tcase, bigger driveshaft to axle yoke, bigger tail pipe, possibly heavier grille, hood vents, blablabla. There's a lot of leather in that thing.

 

5.9 ltd probably only weighs 100-150 more than the 5.2ltd in the same year.

tranny weighs about 25 more, tcase about 5lb more, dshaft about 2-3lb more, sound bar is about 20lbs, engine is the same. No more sound proofing, not much more wiring, same axles, same suspension, same sunroof, seats add a few lbs with the center arm rest in the back.

 

You sure about the engine ? I looked uop the weight for the 318 and its 510lbs loaded, the 360 is 550

 

I actually put my then stock 94 ltd 5.2 , loaded with full spare tow pkg on the truck scale at work . only thing extra in it was a 20lb tool case.
4,140 lbs without me in it .

 

the state registration for my 98 ZJ with the 4.0 says 3820, but since over the years I added a full sized spare, front and rear tow hitches and the gas tank and transfer skid, plus oversize LT tires, I bet its over 4000 now....

 

Wikipedia lies

I weighed my truck at the dump and with a super small 4x6 utility trailer, witch i assume is around 200-300lbs. I weighed in at 4600lbs, so do the math on that and the 4300 for 5.9, would probably be about the same for the 5.2. I cant see the 4.0 causing 800lbs of weight loss vs the magnum motors either, but who knows for sure. I weigh 215lbs also, so 4100lbs + or - a few hundred pounds and that will most likely cover a large percentage of stock ZJ weights

the xj's are a lot lighter

the 4.0s IMO are not turds and are quick enough, they rev a bit smoother then the V8, sure the V8s are quicker, but its a jeep your not going to set the world on fire

 

Wikipedia lies

I weighed my truck at the dump and with a super small 4x6 utility trailer, witch i assume is around 200-300lbs. I weighed in at 4600lbs, so do the math on that and the 4300 for 5.9, would probably be about the same for the 5.2. I cant see the 4.0 causing 800lbs of weight loss vs the magnum motors either, but who knows for sure. I weigh 215lbs also, so 4100lbs + or - a few hundred pounds and that will most likely cover a large percentage of stock ZJ weights

the xj's are a lot lighter

the 4.0s IMO are not turds and are quick enough, they rev a bit smoother then the V8, sure the V8s are quicker, but its a jeep your not going to set the world on fire

I disagree :monsta:

 

From IRO's website

Factoid: We weighed one of our ZJ's with 2" of lift and 31" tires. Why? Because we were curious and it was fun. 4020 lbs!

 

Dodge, happen to know if that is the I6 or V8? That sounds more on par for what I would "think" it should be.

Steve

 

I have a 1995 ZJ Laredo full size spair, a luggage carrier on top loaded with my tools, leather seats, class 3 hitch, 235/75R15 tires, gold waffle rims from an 87 Cherokee, 200 amp alt. 1000amp battery, with everything I have in the truck it weighed 4340lbs

 

I know this is an old thread and all, but somewhere above it says the T-case from a 5.9 is heavier than a 5.2???

 

i think it had a larger main shaft/chain or something. still a nominal difference, but since were here, my pig weigh over 5100 lbs now, it does however put me in the next weight class in VA=an inch more of legal lift height front and rear:rofl:

 

While power to weight ratios are a big factor, you must also include gear ratios (trans. and differential), torque and many engine factors if you are comparing how cars would perform opposed to others
Just try looking at the power to weight ratio of a motorcycle compared to a car. See that the cycle can accelerate more rapidly, but not have the top end speed of the car for instance

You can pull out the slide rules and try to factor in a myriad of stats, but I think you just have to look at it empirically - the 5.2L and 5.9L have enough power for the job, the 4.0 may be a bit on the soft side in performance. I would certainly like the 4.0 gas mileage than my high performing 5.2L though

 

In having the 4.0 in my 96 ZJ, wife's 2000 TJ (sold w/rotted frame), my spare 93 XJ 5-speed, and son's 96 XJ, I'd have to say performance wise my 96 ZJ is the worst as being slow. The XJ's & TJ 4.0 engines seemed to have a whole lot more pep which put my ZJ to shame but their gas mileage sucks compared to my 18mpg w/3.73 gearing. May not be a fair comparison unless you dropped the same 4.0 engine in all 4 Jeeps since they all seemed to run a little different w/various axle gear ratios.

The XJ's are lighter than my 96 ZJ but was surprised to find my wife's short-wheel based rag-top 2000 TJ w/o all the glass windows I have is only 300 lbs lighter. Must be due to the HD frame, wide cross-member which functions as a skid plate, beefier bumpers, heavy stock wheels which are a whole lot deeper, etc..

 

(/QUOTE) From Uniblurb: The XJ's are lighter than my 96 ZJ but was surprised to find my wife's short-wheel based rag-top 2000 TJ w/o all the glass windows I have is only 300 lbs lighter. Must be due to the HD frame, wide cross-member which functions as a skid plate, beefier bumpers, heavy stock wheels which are a whole lot deeper, etc..[/QUOTE]

I assume that since the ZJ is closer to being a uni-body framed vehicle that the beefy frame work on the others narrows the weight gap. My ZJ is sturdy, but does have definite structural weaknesses like featherweight bumpers and definitely less structural steel than its Jeep cousins

Was your '96 ZJ always under-performing?

for 17 years and 200K plus miles I have had a '95 ZJ 4WD 5.2L quadra-trac that is essentially stock that has always been more powerful and faster than needed. It has towed a 2000 lb boat well, climbed well on the trail and on freeways and highways has always accelerated faster than most cars. On the on-ramps it zooms and has passed other cars very easily when passing. I have been all over the mountain roads and off roads of the California Sierra with never a whimper often carrying full camping loads, a canoe and or a pod carrier on top. It accelerates going up mountain passes with ease.
It has always had good throttle response and I can hit 85 mph+ quite quickly if I open it up
Never had an instance where i could consider it slow. Other people who have driven my car are usually impressed with the power especially the ability to accelerate when at highway speeds.
Could yours have a reason for a case of the "slows" - exhaust blockages, compression loss, tranny problems, fuel system problem. damaged or dirty injectors,carbon build up ???

my ZJ I believe has been weighing in the 4320 range at the recycle scale as I remember - I will have to verify that to be a net weight the next time I go there

 

(/QUOTE) Was your '96 ZJ always under-performing?

Could yours have a reason for a case of the "slows" - exhaust blockages, compression loss, tranny problems, fuel system problem. damaged or dirty injectors,carbon build up ???

My 96 4.0 probably hasn't always under-performed and it has 210K miles on the clock. Within the past 1-2 years I've installed a whole new exhaust system including exhaust manifold/header, cleaned the inside of the intake/throttle body/IAC, installed new Bosch 703 injectors with new Bosch fuel pump assembly, did a complete tune-up including new plugs/wires/brass cap w/rotor, new distributor w/new cam sensor, fixed all the oil leaks including rear seal/pan gasket while changing oil every 3K miles since new, etc.. Transmission is strong but I'm on my 3rd PCM.

Have thought about taking it to the local shop and have them smoke the intake while also connecting a drbII scan tool. Just bought a compression tester and I'm going to check compression first. Thanks for the input!

Seems like it's always been a dog though in hauling my small trailer w/an ATV on board.

Yeah, would agree the unibody on my 96 along with the lightweight bumpers tend to take the weight off. Also there's no skids at all on mine. I've always wondered if the Limited's are much heavier than the Laredo's since they seem to be in riding in one?

 

Part of the issue is the illogic in the gear ratios selected by Jeep for the various combinations. The ZJs with the V8 always had a 3.73:1 gear ratio. The ZJs with the 4.0 most often came with 3.55:1, unless they had the tow package from the factory in which case they got the 3.73:1. Now since the V8 had 75 more ft lbs of torque than the 6, the 6 cylinder models should have had more performance oriented gear ratios as standard. Meaning that, the standard gear ratio for the 6 should have been 3.73:1 and tow package 4.10:1.
You can achieve a pretty cheap performance up grade on a 4.0 six ZJ by doing this: next time you get tires, go with a 225/70-15 tire. This tire is the same width as the OE 225/75 but a bit shorter (27.5"tall) yes you will have less clearance but it was a stock size on some ZJs and because the lower height improves the effective gear ratio the engine will seem notably more responsive.

The 3.55s, and the .69 OD ratio in the old school 42RE trans makes them feel slow.
For my second Jeep I went up the ladder a bit as you can see. 375 ft lbs of torque feels real nice and the newer style Chrysler 5 speed trans shifts much faster than the old school ones.

 

Part of the issue is the illogic in the gear ratios selected by Jeep for the various combinations. The ZJs with the V8 always had a 3.73:1 gear ratio. The ZJs with the 4.0 most often came with 3.55:1, unless they had the tow package from the factory in which case they got the 3.73:1. Now since the V8 had 75 more ft lbs of torque than the 6, the 6 cylinder models should have had more performance oriented gear ratios as standard. Meaning that, the standard gear ratio for the 6 should have been 3.73:1 and tow package 4.10:1.
You can achieve a pretty cheap performance up grade on a 4.0 six ZJ by doing this: next time you get tires, go with a 225/70-15 tire. This tire is the same width as the OE 225/75 but a bit shorter (27.5"tall) yes you will have less clearance but it was a stock size on some ZJs and because the lower height improves the effective gear ratio the engine will seem notably more responsive.

The 3.55s, and the .69 OD ratio in the old school 42RE trans makes them feel slow.
For my second Jeep I went up the ladder a bit as you can see. 375 ft lbs of torque feels real nice and the newer style Chrysler 5 speed trans shifts much faster than the old school ones.

My ZJ has always been a runner, my hemi is quick to. The hemi feels a bit less quick, but thats probably a more refined chassis at work, and being stock exhaust vs my wake the dead and then make them deaf exhaust on the ZJ.

FYI, my ZJ on 3.5"s and 31s will walk away from a co workers Jetta 2.5. They are peppy little 5 banger cars, they make about 165whp, and I assume weigh in right at 3,000lbs, as a good comparison for everyone. My ZJ also has the regular fuel chrysler PCM update.

 

I like LouC's comments about matching a tire size to the gearing. Seems quite simple but logical

I have always run 235/SR75-15 on my 5.2L Laredo - up a little from the stock 215 I think. I have a friend wanting me to retool to a 16 inch set up. I did not think that would be wise to tinker with my current set up that works for me.

I did the SeaFoam cleaning (as described in the forum - do a forum search if interested) for my intake system and I did get a big boost in throttle response as I think it cleared a lot of carbon out of the system. Some in the forum are wary of doing this as it can be harsh. It seemed to work for me, but I do not know long term effects. I did not do the SeaFoam in the motor oil but I still may in the near future.

 

I gave the 98 to my son for his 18th b-day, he loves it! If I were keeping it for myself, when the diffs need work, I'd re-gear to 4.10:1 and put a True Trac in the rear, that would make the 4.0 wake up a bit. You know many 4.0 Explorers had 4.10s in them as well. If the 4.0 ZJs had the Chrysler electronic 5 speed trans and the right gearing, they would have been a much better performing vehicle. I like a V8 in the ZJ but that Aluminum D44 was a headache, as was the 249 when the VC locks up. I had no issues with the drivetrain in my 98 as far as the transfer case and diffs in 15 years of driving.

 

The '95 ZJ 5.2 with the quadra trac was my first 4WD or all-WD and I have been totally happy with it for 17 years - usually had Goodyear Wrangler ATS tires on stock wheels- I have had plenty of off road, ice, snow and all weather driving and never had one instance where I was not totally secure with it. I consider my ZJ and just about every aspect of it the best decision I ever made - possibly the gas mileage would be the only area I could have liked more