1. C

    4.0 A/C leak

    Hey everyone, my ac blows pretty mediocre. Cold, but not cold eneugh for Florida heat. I recharged about 4 months ago and it is pretty consistent with air temp. It’s tolerable but not the best. I tracked down the leak, but I don’t know what this specific part is called. There are 2 places that...
  2. SolarYellowshortbuss

    PCM failure?

    For the past forever ive been having issues with my wrangler from it saying I dont have a fuse, the oil pressure gauge going up and down, to the wrangler starting up very quickly one day to nothing but cranking a few days later. I took it to a fella who ran the codes for me and he says the brain...
  3. SolarYellowshortbuss

    Jeep randomly doesnt wanna start

    Ive been chasing this problem for 2 months now at random times my Jeep doesn't wanna start I've replaced the fuel pump, relays, and made sure the fuel pump connection wasnt bad Ive been stranded twice now and the same thing happened those two time crank crank crank crank crank just refusal to...
  4. SolarYellowshortbuss

    4.0 doesn't wanna turn over good when cold.

    My 2003 TJ with the 4.0 has been not wanting to turn over on the first crank when the engines cold it does always start on the 2nd or 3rd crank. Thanks in advance
  5. L

    97-06 4.0 automatic wiring harness differences?

    Hey, I bought a 2002 tj 4.0 with 32rh automatic, the po replaced the transmission(I don't know if he used thr right year model, or if the year matters) but he said after that he couldnt get it to run and said it was not getting power to the fuel pump! He cut and hacked up the factory wiring...
  6. J

    Junkyard motor or crate engine?

    Hi yall! I have a 1998 4.0 TJ with 183k miles, sadly the engine overheated while I was driving one day, took it to a shop, they quoted me 1k to fix the head gasket and resurface the head, I’m debating if it’s worth just investing into a crate motor, I don’t want to replace the head gasket and...
  7. MrV7

    Transmission Reinstalled, Jeep won't start

    Ahoy! SoI finally got my new clutch, fly wheel, and old transmission/transfer case put back in the LJ. Went to turn her over and she did not want to start. 4.0, 6speed, 231 Battery is reading 12.7, can hear the starter pop out. Shifters in neutral, clutch pushed in, go to turn the key and...
  8. W

    Input shaft not aligning to pilot bearing

    Hey, guys, my input shaft isn't going into the pilot bearing on my '98. 4.0, 5-speed, clutch is lined up it's just that the input shaft will not line up to the bearing. I used the clutch alignment tool, splines are on the transmission shaft. Pictured below is how much I have left to go before...
  9. W

    Hydraulic cylinder attached to steering, I don't think its hydro assist?

    Hey, everyone. I've got what's essentially a stock TJ here and it has this cylinder attached to the steering. These are pictures taken from the modded one I bought, swapping engines and lift and all due to bad frame. They both have this, and I don't think it's hydro assist, because it looks...
  10. G

    Bad Manual PCM?

    I have an 06 4.0 manual that is bone stock (yes, original owner). When starting out, the Jeep has started to stall and even die (pretty embarrassing in traffic). When it dies, depressing the clutch will not save it, but it will fire right back up. After a couple months of very light driving, it...
  11. D

    Is there anyway to get a 4.0 to sound good at all?

    I’m a big fan of Jeep 4.0 so I can’t bring myself to change out the engine but a sick sound matters a lot to me I’m not sure why but it just does, I’ve been told that there isn’t a way to get it to sound good but I figure I’d ask you guys instead of just a bunch of locals thanks in advance.
  12. B

    Utah Sold

    The TJR has been sold. Thank you to all the great members on this site, maybe one day I will be back
  13. Rdelcampo19

    Will a 0331 TUPY head from a 2004 TJ work on a 1999 XJ 4.0 block?

    How’s it going, quick question. Trying to build a 4.0 to have as a spare for my 04 TJ. I picked up a good 115k mi. 4.0 block that was originally from a 99 XJ. I’m trying to find a head and found a 0331 “TUPY” head from a 04 TJ, would that head work? ** Side note: any guides or pointers would be...
  14. Marklar1983

    SOLD Bitchin' Red 97 TJ Needs Good Home

    1997 TJ for sale. Mildly built. Great trail runner, daily driver, and starting point for a hardcore build. I’ve owned this Jeep for over a decade and driven all over the hills forests around Reno. Lots of good memories, but now that I’m a family man, it’s time to serious-up; I got an LJ to fit...
  15. Lorado

    Continuing oil pressure issue with 4.0

    Hi all A little over a year ago I bought a 97 tj sport 4.0 manual. It currently has 135k on it. When I first got it I noticed low oil pressure when warm so I started with the pressure sender, then a high flow oil pump. Then this past weekend finally got around to main bearings and then a...
  16. Firecaige

    Would a NV3550 from a Liberty fit on a 99 TJ 4.0?

    So I have thought long and hard about the swap but I was wondering if I could just use the nv3550 from the liberty sport or if it would have to be from a wrangler. I really want to know because the price difference is insane.
  17. dogdaddy123

    P0201 head scratcher

    Inspected fuel injector on 1, and replaced it, there is no power coming to the injector harness connection after checking with a noid, all others are working fine, just this one is dead, inspected the wiring back to the back of the engine before it goes into the split and connectors and no...
  18. jw_LJ

    Another TJ 4.0 Misfire Thread (2005 LJ)

    Hello everybody, I've been visiting the forum for years and have learned so much through this amazing site, and I finally am coming to you guys about an issue I've been having for years now. While I want to provide as much information as possible, I will keep it as brief as possible. I hope you...
  19. F

    Bell housing & rear main questions

    Tracing a lower engine knocking/ticking and checking the tightness of the bolts on what I believe is the bell housing? The bottom right bolt upon trying to tighten just continuously spins instead of getting tighter. It is in place and not freely moving around but it is not snug at all and...
  20. SolarYellowshortbuss

    Overheating and smoke coming from radiator fins

    So another day another problem I was driving home and once I started to pull into my driveway my engine started overheating into the red im not sure where to start tho any help would be appreciated. It’s also got the 4 liter