Flag waving: XJ AMC 80s vs Chrysler's era XJs

[rainer]

I have an 89 that has 150k miles on it that runs like crap. Tempermental as can be. Have a 95 that has 218k miles and runs like a dream. My 2000 has 95k miles on it and runs like the day it was purchased. All in all I prefer the later XJ's over the old Renix machines. I have had my share of both. I have owned nothing but XJ's over the last ten years or so. My 89 stumbles and lops at idle. it doesn't warm up properly. It's a real nightmare on the cold winter days.
Just my $.02 worth!

 

[CMNCHE]

clutch pedal on my 89 broke off at the top. it was only held on with 2 tack welds.

i have 208k on mine without any major problems.

Now that would suck in the middle of nowhere.

 

[rockwerks]

I have an 89 that has 150k miles on it that runs like crap. Tempermental as can be. Have a 95 that has 218k miles and runs like a dream. My 2000 has 95k miles on it and runs like the day it was purchased. All in all I prefer the later XJ's over the old Renix machines. I have had my share of both. I have owned nothing but XJ's over the last ten years or so. My 89 stumbles and lops at idle. it doesn't warm up properly. It's a real nightmare on the cold winter days.
Just my $.02 worth!

so some maintance...........get codes and fix stuff..........its amazing what a little effort to a 18 year old rig will do

 

[rainer]

If you can pull the codes on my 89 you're a better man than I.

 

[XJHummerRescue]

If you can pull the codes on my 89 you're a better man than I.

Sure can, just buy this http://cgi.ebay.com/ebaymotors/DRB-...ryZ43989QQssPageNameZWDVWQQrdZ1QQcmdZViewItem and then get a hold of an adapter for '87-'90 Jeeps and you're set

 

[rockwerks]

Sure can, just buy this http://cgi.ebay.com/ebaymotors/DRB-...ryZ43989QQssPageNameZWDVWQQrdZ1QQcmdZViewItem and then get a hold of an adapter for '87-'90 Jeeps and you're set

UMMMMMM.from what Ive read that will not scan the renix system.

but I take mine to the dealer and for a 25.00 fee they scan and give me the codes

 

[Rick Anderson]

Perhaps I'm biased, since I'm a long time Chrysler owner/fan before I ever got into Jeep.

I'm guessing Chrylser did not put in the effort to bring the AMC engines into the fold that they should have, and thus the AMC motors declined in durability and quality, compared to the other Chrysler motors.

The Chrysler Motors of that era and today easily are very fresh at 100k+ miles and last long past the 200k+ mile mark.

You fellas may know better than I, but how are the new Jeep Platforms doing? From what I hear they are nice, perhaps they are not "It's a Jeep Thing, You Wouldn't Understand", but I think its a case of Chrysler taking full ownership of the Jeep line, no more of re-using some of the bastard AMC motors, they are their motors and their technology, or at least what is used from AMC has been Chrysler's long enough, that they have integrated it.

 

[casm]

You fellas may know better than I, but how are the new Jeep Platforms doing?

If we're just talking about the '97-up XJs, I'm more than happy with my 2000 Limited which is currently just a few hundred miles shy of 100,000. Even my previous 2001 (totalled) which was at around 103,000 when it went swimming felt bulletproof. Between the two I've put somewhere in the region of 60K on them and both have good compression and no leaks at those mileages.

Having said that, as an exercise in comparison a friend of mine picked up an '89 Limited a few months ago with somewhere around 170,000 on the clock; it's now up around 180,000. Overall condition is comparable to mine as far as leaks and compression go, but we've been through a few items you'd expect to have go at those mileages - coolant bottle, water pump, valve cover gasket. Other than that, it's pulling strong and is probably slightly less than halfway through its usable life without major overhauling.

If we're talking about post-XJ Jeeps - well, I really don't have as much authority on them, but anecdotally the longer-term KJ owners I know have had no serious issues, but the WK people aren't as happy with theirs as the WJ owners. Seems to be a pattern with the Grands.

From what I hear they are nice, perhaps they are not "It's a Jeep Thing, You Wouldn't Understand", but I think its a case of Chrysler taking full ownership of the Jeep line, no more of re-using some of the bastard AMC motors, they are their motors and their technology, or at least what is used from AMC has been Chrysler's long enough, that they have integrated it.

My only real beef is that Chrysler dropped live-axle front suspension except for the Wranglers. Big mistake. They could've engineered a modular IFS for the 2WD KJs and WKs that would've been compatible with a slot-in live axle for the 4WD models.

 

[rainer]

Where I live none of the dealers have the equipment to scan the Renix System. The only one who had it was an old AMC Jeep dealer who no longer exists. The Chrysler dealers didn't see it fit to buy the Scan equipment so now we are on our own around here!

 

[Rick Anderson]

My only real beef is that Chrysler dropped live-axle front suspension except for the Wranglers. Big mistake. They could've engineered a modular IFS for the 2WD KJs and WKs that would've been compatible with a slot-in live axle for the 4WD models.

OK, I'm probably going to really show my 4WD Ignorance here, But why is IFS bad for 4WD? The HMVV's have 4 wheel independent suspension, as well, the new 7 ton Truck for the Military has 6 wheel independent suspension (pretty awesome suspension and drivetrain on that truck).

I would think Independent Suspension would give you more traction and control off road, than live axles.

Is it a case of strength and ruggitness? That most Independent Supsensions from the Major Manufacturers just don't have the strength or travel length for serous off-roading? Thus, the live axle is preferred, since they won't break and give you more flexibility and ability to modify, than the whimpy Independent suspensions you'd otherwise get from manufacturer?

I can see this being a reason to prefer a live axle over an independent suspension. Is it true that a properly designed independent suspension is better than a live axle in off roading? The modern military vehicles seem to indicate such is true.

 

[casm]

OK, I'm probably going to really show my 4WD Ignorance here, But why is IFS bad for 4WD?

IFS itself isn't inherently bad; how it's implemented can make it less desirable. More:

The HMVV's have 4 wheel independent suspension,

Correct, but look at how it's done on the Hummer - it's closer to a portal axle arrangement as opposed to A-arms (like on a KJ). This leaves less stuff under the truck to smash on obstacles. There are also articulation issues with IFS that don't crop up with live axles, as well as suspension and subframe ones that you start getting into with lifting.

as well, the new 7 ton Truck for the Military has 6 wheel independent suspension (pretty awesome suspension and drivetrain on that truck).

Don't know anything about this one - got a link?

I would think Independent Suspension would give you more traction and control off road, than live axles.

Based on vehicles I've owned, I far prefer a live axle than IFS for off-road work - and I'm basing this on two Series IIA Land-Rovers, Series I Range Rover, and two XJs vs. a Nissan Patrol, Lada Niva, and Subaru Brat, so there's a pretty wide spread of stuff in there. The last IFS 4x4 I drove was a current-model Nissan Frontier; while it felt great on the freeway, the IFS (as well as the traction/stability control stuff; that's a rant for another time) encouraged me to over-drive the truck's handling capabilities because it felt so car-like, and I just didn't care for how it operated off-road. Having said that, I've had some minor stick time in an H1 Alpha and came away very impressed with its capabilities, even if the thing was FREAKING HUGE.

Is it a case of strength and ruggitness? That most Independent Supsensions from the Major Manufacturers just don't have the strength or travel length for serous off-roading?

This is part of it, sure.

Thus, the live axle is preferred, since they won't break and give you more flexibility and ability to modify, than the whimpy Independent suspensions you'd otherwise get from manufacturer?

A good independent setup will outperform a poor-to-mediocre live axle setup. The problem with the IFS (IMHO) used on most 4x4s on the market today is that the basic designs tend to be derived from designs used on passenger cars; take a look at the current Land-Rover Discovery for a depressing example of this. Independent suspension can work very successfully for off-road use, but not when it robs clearance and articulation.

 

[GreenXJ2K]

http://detr6oit.50megs.com/ifs1.html
http://www.billhughes.com/XJversusKJ.jpg

seems pretty clear

 

[87manche]

in defense of IFS in those pictures it seems that the live axle setups were both more heavily modified. The KJ seems to have the swaybard still coneected, and that XJ is nasty looking, compared to what looks to be a mostly stock KJ.

 

[GreenXJ2K]

"in defense of IFS in those pictures it seems that the live axle setups were both more heavily modified. The KJ seems to have the swaybard still coneected, and that XJ is nasty looking, compared to what looks to be a mostly stock KJ."


Fully agree, maybe it wasnt the best representation, but nonetheless it does show the advantages of solid axles vs IFS especially in the rough stuff. IFS does offer more stability if your off roading at high speeds. (ie Jeepspeed type off roading)

john

 

[87manche]

"in defense of IFS in those pictures it seems that the live axle setups were both more heavily modified. The KJ seems to have the swaybard still coneected, and that XJ is nasty looking, compared to what looks to be a mostly stock KJ."


Fully agree, maybe it wasnt the best representation, but nonetheless it does show the advantages of solid axles vs IFS especially in the rough stuff. IFS does offer more stability if your off roading at high speeds. (ie Jeepspeed type off roading)

john

Agreed, that's why prerunning trucks almost all have IFS . I like the simplicity of live axles, solid axle shafts and no CV joints to explode or bind at severe angles.
I've seen some IFS trucks that were pretty capable though.

 

[Rick Anderson]

I have to agree with GreenXJ2K, those pics looked a little rigged in favor of the live axle setups.

BUT, those pictures do make something apperant to me. Those live axle trucks were getting that articulation with probably only a couple of hundreds of dollars of modifications to their rigs. The IFS vehicles looked like they could only achieve the same by throwing away the existing IFS and fabricating an entire new one, with body and drivetrain modifications to mount it, probably costing thousands of dollars.

I'm getting the picture, Thanks CASM, I agree, nothing inheritently wrong with IFS, just the IFS on available vehicles does not lend itself to serous off roading while the live axle setups can be easily modified for off-roading much easier.

Oh the 7 ton truck, the 7-Ton Medium Tactical Vehicle Replacement (MTVR) is made by Oshkosh Trucks.

http://www.globalsecurity.org/military/systems/ground/mtvr-pics.htm
http://www.oshkoshtruck.com/pdf/Oshkosh_MTVR_brochure.pdf

With the Oshkosh TAK- 4™ Independent Suspension System, the MTVR achieves levels of perf o rmance never before realized in a tactical wheeled vehicle, enabling the MTVR to traverse terrain previously re g a rded as impassible by military trucks.

I haven't found any pics of the suspension, I'll have to continue to look, but I've seen it in person and from a muscle car guy, I have to tell you, its pretty impressive setup for the suspension and drivetrain.

 

[Jim D.]

Great thread evolution; pleased that so many folks take the time to contribute. As for me, personally, I still like my '97 better than the '87. But, I'm prepared to attribute that to mostly roading it, and to 10 years of perfecting and evolution applied to what was really special from day one.