Eagle

If down time has to be minimized, you need the easiest, fastest swap or conversion you can find. That means that a 4.3L V6 is NOT a candidate. It was never used in the XJ/MJ. It's a completely different block (essentially a shortened small-block V8) that will require fabricating motor mounts, different transmission and/or adapters, different fuel delivery system -- it's as much work as doing a Chevy V8. For what it's worth, in the early days of NAXJA another member who lives about 5 miles from me was driving an 86 XJ with a 4.3L V6. I asked him if he thought it was a good conversion. He rolled his eyes and said "Never again!" Even a 3.1L or 3.4L GM V6 will require some work. You would have to rebalance your flywheel to use with those engines, and that means a machine shop bill. Now -- Pay attention to what we write and don't read what you want to read. The Jeep 2.5L is NOT -- I repeat NOT -- the GM Iron Duke 2.5L engine. You do NOT want a GM 2.5L engine. You need a Jeep/AMC 2.5L out of a Cherokee, Comanche, Wrangler, or Dodge Dakota. That engine was used in the MJ, even the '86, so physically it will bolt in with no adapters and no custom mounts. It will work with your transmission with no adapters -- the bell housing bolt pattern is the same. As I posted above, the oldest version (only in XJs) used a carburetor. Your best choice would be the MPFI engine, but that would mean a bit more work because you'll also have to get the engine room wiring harness and ECU to run it. Back in the late 1990s, Jeep was selling a MPFI conversion for the 4.2L Wrangler I6 engine, which came from the factory with a carburetor. The conversion kit was basically the MPFI setup and engine room harness from the newer, 1994 Wrangler with the 4.0L engine. So ... if the controls for the 1994 4.0L can be split out and used as a stand-alone conversion, if you get a 2.5L with the wiring harness I see no reason you can't install that as a stand-alone. If you are considering the mid-generation of the 2.5L with the throttle-body injection, consider that if the injector goes bad it sells for about $130. The newer MPFI models use the same injectors as the 4.0L engines of the same years.

1993–1995 Chevrolet Camaro 1993–1995 Pontiac Firebird Plus 1984 - 2000 Jeep Cherokee/Comanche 2.5L (I don't think they offered the 2.5L in 2001. It was used through 2003 in the Wrangler.) Yeah, yeah, I know -- it's only a 4-cylinder and you have six. Consider this: 1984-1986 2.8L V6: 115 hp @ 4,800 RPM, and 145 ft-lbs of torque @ 2,400 RPM 1984-1985 2.5L I4: 105 hp @ 5,000 RPM, and 132 ft-lbs of torque @ 2,800 RPM (Carbureted) 1986-____ 2.5L I4: 105 hp @ 5,000 RPM, and 132 ft-lbs of torque @ 2,800 RPM (TBI) 1987-1990 2.5L I4: 121 hp @ 5,250 RPM, and 141 ft-lbs of torque @ 3,250 RPM (TBI) 1991-2003 2.5L I4: 130 hp @ 5,250 RPM, and 150 ft-lbs of torque @ 3,250 RPM (MPFI) You can see that even the original, carbureted version of the 2.5L is very nearly equal to the 2.8L V6. Once you get the 1987 the 4-cylinder out-performs the V6, and the 1991 and newer multiport version is significantly better than the V6 in horsepower, as well as slightly better in torque. The 2.5L will bolt right up to your transmission, and it won't eat it. You can also find the same 2.5L engine in Dodge Dakota pickups of the same vintage.

Or even a late model Cherokee 2.5L

Maybe -- maybe not. I once threw a used engine into an old Javelin. It had sat long enough under wet enough conditions that the rings were rusted to the cylinder walls. The car was a clunker that I just wanted to get running, so I pulled the head, soaked the cylinders liberally with penetrating oil for a couple of days, used a 2x4 and a heavy ball pein hammer to break the rings loose, then I cut the ridges off the tops of the cylinders and honed the walls with the pistons in place. Put it back together and after a couple of hours of (re)break-in it didn't even smoke.

Even if you get one out of a 2001 XJ (which will have the new-style, inferior, vibration-prone output shaft), it will be 13 years old. Why not just put a chain in the one you have?

2000 is a baby. How many miles are on the engine and why do you think it needs a rebuild?

You need an engine. Quit throwing time and money at that boat anchor and find yourself a decent Camaro 3.4L with fuel injection.

The ratio on the manual boxes was something like 20:1 or 24:1. The ratio on the power boxes is 14:1, and I prefer the ZJ box with a 12.7:1 ratio and I'd be even happier with a 10:1 ratio. Don't go looking for a manual box ... you WON'T like it.

And Chrysler used the 8.25 in vehicles other than the Cherokee ...

3.5 V6? What engine is that? It's not one I've ever heard of.

That's how I stopped mine from leaking -- silicone. Which means if I ever open them I'll have to reseal them, but after 26 years if I haven't had to open them yet, it's unlikely I'll ever need to.

You're making a big mistake. They leak. All of them. All the time. The wing vents on my '88 XJ leaked from the day I took delivery (new). After several complaints at the dealership, the Chrysler field rep offered to "fix" them ... by replacing them with the non-operable windows.

What size tires do you plan to run? IMHO, if you want more balls than the 4.0L offers you need more than gears -- you need an LT1.

Unless something has changed recently, the highest (numerical) ratio you can get for the Dana 30 front axle is 4.88 -- and that's only available from aftermarket gear makers, not from Dana-Spicer. Beyond that, the pinion gets too small to be useful.

Only if it comes from a '97 or newer XJ. The newer ones have larger axle shafts. The older 8.25 has the same shaft diameter and spline count as the D35. The housing is stronger, but the internals aren't much better. If you're going to do it, do it once. So if I swap it I should go with a post 97? I'm pretty sure that's what I wrote.

If whatever damage it suffered was repaired properly, IMHO $4200 for a '99 XJ with only 106,000 miles on it is a GOOD price. They're selling for more than that around here with higher mileage. His gas mileage claims, however, are pure fantasy. As someone said, expect maybe 17-20 mpg. Check the front footwells from underneath for rust. The XJ is just as likely to rust out there as an MJ.

Only if it comes from a '97 or newer XJ. The newer ones have larger axle shafts. The older 8.25 has the same shaft diameter and spline count as the D35. The housing is stronger, but the internals aren't much better. If you're going to do it, do it once.

Would you suggest a tune up after I do this? A tune up? No, you will need to run it on a dyno, monitoring the fuel-air mix, and very likely you'll need to rejet the carburetor, and possibly rework the advance springs in the distributor. so all this just to go to straight pipes??? Yes, if he wants to have it run right and not burn the valves due to a constant lean-burn condition.

That's C200 for the ECU. According to the factory electrical manual, dealer-installed air only used two connections off the ECU: #22, A/C Clutch; and #30, A/C Control Switch

Stuck starter solenoid.

Would you suggest a tune up after I do this? A tune up? No, you will need to run it on a dyno, monitoring the fuel-air mix, and very likely you'll need to rejet the carburetor, and possibly rework the advance springs in the distributor.

Obviously, you're not looking in the right places. According to the twit in the video, they're everywhere and people are giving them away.

Okay, you caught me. To what address shall I send my man card?

If it's left on too long or you use too much, the stripper will definitely eat into aluminum. I think it says that in the instructions.

5-liter Mustang.