richamor

My 89 has developed a noise that sounds like a lifter or a rod starting to knock. It has been run hot and the oil pump recently failed, which has led to the current issues. It is still driveable and runs good except for the noise. It does vary off and on but still doesn't smoke.

But we want to use this as a tow vehicle for our small camper. It weighs about 2000 lbs fully loaded. We are approaching retirement and want to travel. Really really really like the XJ. Plenty of room, interior like new, everything works as it should. Just put new ball joints, shocks, and tires. Rides and drives great. We don't really plan to go off roading.

The motor is the problem. I've looked at a stock rebuild, a stroker build, a MB om617 install, maybe a forced induction stocker. Pros and cons to each one. I also plan to replace the AX15 with a 700R4 at the same time. I will keep the Jeep drivable while I work on the new motor.

At the moment I am liking the idea of a blown stocker. Either turbo or supercharger. Should be plenty of power and durable if done properly. The om617 is enticing, but seems to be a lot of work and somewhat costly. The stroker makes plenty of power and is not cost prohibitive. Durability maybe an issue??

I am undecided at the moment. Cost, durability, and performance are all issues. Economy is also an issue since it only gets around 17mpg now. With a trailer that would be cut in half. That makes the diesel sound like a clear winner maybe, but I am interested in other opinions.

aflemke

Personally, I would stick with a stock rebuild. Simpler, and proven reliability; especially for long road trips. I would like the peace of mind. The stock engine seems to have enough power for 2000 pounds.

thatXJguy

The only issue, actually, is cost.

All three engines last forever. Diesel, stroker, or stock. But it's all depending on what kind of money you want to shell out.

A diesel swap will be thousands of dollars. You have to convert a lot of stuff to make it work. A stroker swap is the second most pricey, as you'll need to upgrade your computer, injector, induction, and more along with the pricier engine, and the stock replacement is the most affordable and still lasts forever.

Rogue4x4

Stock. Best option for your needs. All other options you listed you're going to be throwing a checkbook at to do it properly. The stock option you'll get the most bang for your buck.

XJlimitedx99

A diesel would be the coolest and best for towing, but also the most labor intensive and expensive. You better know what you're doing for that one.

A stroker would be easier in the sense that the motor mounts and wire harness would work. There should be no issues with durability if it's built correctly and to last. Again, cost would be high from motor rebuild plus exhaust, intake, etc, etc.

I think a forced induction stocker is too much work for what it's worth. Maybe I'm biased but I just like the simplicity of natural aspiration.

A rebuilt stocker would be the most convenient and cost friendly, but if you're going through all the work of rebuilding then you might as well get some extra out of it IMO.

I vote stroker.

Tsaani97xj

Rebuild + gears my vote.

Fred/N0AZZ

A Stock "Quality Rebuild" from a custom rebuilder or a new "Crate Motor" from Jeep/Chrysler that way if your traveling you have warranty honored coast to coast at any Dealership. A solid engine/warranty combo would be hard to beat that is good at a dealership as far as parts and someone who knows the engine well.


As far as transmissions I would stick with the AW4 rebuilt by a good shop for towing with HD parts and Tq/Converter as all your towing is a 1 ton trailer. That along with a HD trans cooler should have you covered without modding for a 700R4. You will need at least 3.73 or 4.10 gears for towing, if it were me and I were using a 6cyd I would opt for the 4.10's less strain on the engine.

extrashaky

You do not necessarily need a new computer with a stroker. I'm running the stock computer with my 4.6L with no issues. You do need upgraded injectors or else you don't get enough fuel to make the power. A bored throttle body is not absolutely necessary but desirable. Both of those items can be had pretty cheap.

Otherwise, a stroker can be run with the stock intake and exhaust if you just want a "stock plus" setup with better horsepower and torque. Just because you put a stroker in it does not mean you need a cold air intake or a header or new exhaust. I went all out with mine, but that's because I wanted the full effect. I could see an argument for a tamer build, especially if it were for towing a camper on long trips with family members who might not appreciate the extra noise.

richamor

I like the sound of this. But the gas mileage with 4:10 gears

Crazy 8s

I'd vote for a quality, performance-minded 4.0 rebuild/remanned combined with exhaust and intake/fuel upgrades. Put money into rear disc brakes and suspension bolstering....and a bumpin' stereo system!

Fred/N0AZZ

Less of a gear than these with a trailer will suck up even more fuel. The 3.73's came stock with every towing package Jeep offered, I have them in my 04 GC "Overland" as well but with a 4.7HO V-8.


The reason I suggested the 4.10 was I thought that you would be carrying even more weight when you head out on a long trip other than the trailer. They also help you slow down as well when at times.

salad

Is the rest of the Jeep stock? Consider the following:

- The OM617 is a nice engine for an XJ but it doesn't make a ton of power. Parts availability for a 40 year old Benz diesel isn't exactly like the venerable Jeep 4.0

- The OM617 is a front-sump engine. This means that the bulk of the sump collides with the front axle. If you don't already have a lift, you're looking at going up 3" just to make it fit. 2" can be done with signifcant fabrication to the front end. If you hadn't done that already it's probably a game changer for a retiree's highway vehicle.

- Towing 2000 lbs on a regular basis with a 4.0L will leave you wanting gears. That's some bucks to do properly.

Your most cost-effective option is a good used engine with the next deepest axles.

If you were already budgeting a rebuild, I'd expand the scope into a MILD stroker. More power out of mostly the same parts with mostly the same reliability. No cam, no valve mods, no computer nonsense. Crank, rods, injectors, throttle body. This is the "poor man's stroker". You'll get more power and it can be serviced anywhere, or at least the parts can be found all over North America.

Don't forget to tune up your brakes and add a transmission cooler!

richamor

I'm looking at the HP25 from Rock Auto. It says from "Famous Maker" but for sure it's an ATK HP25. For $2792.00 delivered to the house. Summit sells it for 2849 and free shipping, so I guess that's a wash as far as price is concerned. both have the 3yr unlimited mileage warranty. I am having some trouble convincing myself 15HP and 50ft/lbs are worth the extra grand. I guess that's why I'm still thinking about it. I also don't like having to run 92 octane.

Really looking at the ATK DA23 stock 4.0 for around $1550 delivered. I like the reliability factor of stock, regular gas, much cheaper price that would offset the cost of gears. And the lower compression would allow for some forced induction in the future if more power is needed.

I do plan to convert the cooling system to a late model open system, so that will mean a new radiator.

The rest of the Jeep is bone stock. I can do the gears myself, and a late model rear with disc brakes may be in the future.

There is a tranny cooler on and I plan to install an oil cooler as well.

Thanks for all of the help guys. I appreciate it!!!!

andrewmp6

I say rebuilt stocker with a better cam or ls swap in it.

richamor

Just looking at it from a value standpoint, I can do a new stock engine with a warranty, 4:10 gear rebuild front and rear, new 99+ intake and bored throttle body, and maybe headers for about the cost of the stroker.

I'm just about sold on that. I'm gonna make some inquiries about a cam upgrade though.

Any suggestions????