OK Forgive me I'm new to both the offroading world AND the Jeep world (I come from lowered VWs and track-prepped Toyota/Hondas :Wow1: )
So all these terms you're throwing at me are a little hard to follow at first...I feel like such a noob
I'm assuming the Dana 35 only came in 90 and older XJs? So thats easy to weed those out..
AW4/NP are what?
Definetly want the 4.0 in an XJ, I've heard so many good things about them and my dad owned two XJs when we were little, one auto, one manual, sold them both to save gas and because the headliner was falling in on the auto but they were perfectly mechanically sound when we sold them. So I'm partial to that motor and overall vehicle...
Contrasting I look the ZJ as well for its niceties and my friend had a V8 ZJ I was quite fond of in high school. So if I got a ZJ I'd probably want the V8. The other thing I like about ZJ's is the four corner coil suspension, not a fan of leafs coming from the car world haha.
What exactly is so bad about the tcase the V8 came with?
Also, how can I tell which tcase/trans are in these cars when I go to inspect them? I gaurantee these owners aren't going to know. They probably dont even know how many damn cylinders it has! Trying to get my hands on an unmolested Jeep that someone was just using as a daily driver and serviced regularly.
I'll try and answer your Q's in order.....
Dana 35 rear diff/axles came in both non-C clip (very early) and C-clip designs (post 94?) in nearly all(not those with Heavy Duty tow package - these had the strong Dana 44) XJ's till about 97 then the Chrysler Corp. 8.25" was used a better diff..... All ABS XJ's had Dana 35's, so 97 to 01 had either 8.25" or D35. The main fault with D35's is the very skinny axle shafts that snap and with a C-clip design you lose the whole wheel and axle stump off the car....this can be VERY inconvenient! There are fixes, you can buy 40% stronger alloy shafts or 110% stronger thicker alloy shafts and larger bearings - but you also need a new diff centre. You can also get C-clip eliminator kits that convert it to a standard pressed-on bearing and bolt on axle. You still have thin wall axle tubes and a semi-flexible casing.......Having said all those horrible things I never had a problem or broke an axle - they mostly snap when used with auto lockers ("lunch box lockers") - so don't fit auto lockers! I changed to alloy shafts when the axle shafts were scored by bad bearings and I've got an manual locker and the standard LSD. Later ZJ V8's had the Dana 44HD also called the Dana 44A because the centre is aluminium and prone to cracking, axle tubes are a press fit and can bend or break casing, internals and shafts are strong but different to the Dana 44 and there is very little after market support for the D44A, e.g. no lockers made for it.
AW4 = Aisin-Warner Type 40 auto transmission a very good tranny fitted to all auto 4.0L XJ's....you can't manually select for downhill engine breaking, it'll shift up to 2.
Only early 4.0L ZJ's had AW4's, later ones had the Chrysler 42RE, an OK-ish auto with a better manual selection of all gears and selectable Overdrive. V8 ZJ's had the strong 46RE a heavy duty version. These are modern versions of the Torqueflite 727, with electronic controls.
NP = New Process, later became NV, New Venture (same thing exactly), the manufacturers of all transfer cases in Jeeps of this era, and many other U.S. makes. XJ's had either NP231 or NP242 transfer cases, ZJ 4.0L's had either NP231, 242 or 249 types. ZJ V8's usually came with 249 type, but you can find all 3 types in ZJ's and you can swap all of them into any XJ or ZJ. Read posts above re. 249's. How to tell what's in a car? - Simple, look at the selector. A 231 will read 2WD -N- 4WD Hi - 4WD Lo. A 242 will read 2WD- N - 4WD PT- 4WD FT- 4WD Lo. A 249 will have Hi Full Time - N - 4WD Lo, in 4WD Hi there is automatic centre differential action via a viscous coupling, in 4WD Lo the viscous coupling is mechanically locked up post 96 (pre 96 it continues to function)
The 4.0 is a great engine and very tough and longlasting, quite powerful in the standard light XJ. The 4.0 in the ZJ was tuned for more low down torque according to Jeep. The 4.0 is adequate in ZJ's but longer lasting than the more powerful 5.2/318 V8 (approx 30 h.p. more) or the rarer 5.9/360 V8 ( +50 h.p.). The V8's use more fuel, but not much more in a heavily loaded ZJ. The later 4.7 V8 (totally new design) in WJ's is not an engine I would choose for longevity and toughness.
You're right about the 4 coils on ZJ's, plus they had 4 wheel discs (pre 94 had rear drums) with ABS, the Limiteds had better seats with 12-way electrics and some useful stuff like the EVIC to monitor a lot of fluid levels, functions etc and a trip computer.
Good luck, I hope this helped.
Kinda a toss up between the 231 and the 242 t-cases... I think more after market suppost for the 231 but no big deal. Lots of folks start to wrap their heads around the high vs low pinion front axle... I don't really see why. Its ok either way but not the end all to die for.
