1987 Comanche 2.5L

[railroad sam]

Reaching out for help here. I'm the proud owner of a 1987 Comanche. It has the 2.5L, Metric Ton Package, 4WD, and long bed. I bought this truck new. It has served me well. At about 80k miles I had a piston to blow. Engine cylinder was machined and sleeved by our local race car machinist. All work done by a qualified mechanic. Transmission was also replaced a little later with new throw out bearing and clutch.

Well number two piston has just done the same thing. Blew up and chewed up spark plug. I've always wanted the 4.0L engine in this truck. Engine has 201K miles now.

Men, what are my options? From what I've read. Thinking I should go back with a rebuilt 2.5L engine. Seems this might be the easiest and least expensive way.

 

Thanks,

Railroad Sam

[Eagle]

A rebuilt 2.5L would be the least expensive route, as well as the easiest. But ... in terms of difficulty, a 4.0L swap would cost more because you would have to also obtain a matching transmission, as well as a new ECU and wiring harness, but the cost of freshening up a 4.0L shouldn't be orders of magnitude greater than a 2.5L. They are, after all, basically the same engine.

 

In fact, I'm struggling with the same decision right now. And I'm no closer to a decision today than I was eight months ago when all Jeep projects came to a screeching halt when I was admitted to the hospital for an acute gallbladder attack. I need to decide soon so I can start gearing up for the project this summer.

[johnj92131]

My suggestion would be to go with the rebuilt 4 cylinder engine.  It is the most cost effective thing.

 

If you go with the 4.0, you will need to replace your transmission with an AX-15 at the same time.

 

Edit:

 

As I was writing this Eagle posted the same advice!

[railroad sam]

Well men. Dropped in a new long block and replaced water pump and alternator. New hoses and belt. Runs good. Still a dog on speed. 85MPh tops. But still proud of her.

Thanks for all the advice.

 

Railroad Sam

[Jtrux]

Where do you work? I used to be a carman for Union Pacific.

 

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[railroad sam]

Jtrux. Been and still railroading since 1978. Fort Worth and Denver Railroad. Burlington Northern bought us in 1981. We bought the Santa Fe in 1995. Now Warren Buffett owns us. Conductor out of Wichita Falls, Texas running to Amarillo. When not on my Harley in my 1987 MJ 4wd long bed metric ton. Bought it new in Fort Worth. Union Pacific carmen in Ft. Worth and in Nebraska used MJ trucks.