johnj92131

The Comanche has been my Home Depot truck and spare driver since 2007. Since I am getting near the decision point to put a new stroker motor in the truck or to simply replace the Comanche with another truck and move on. Here is my thinking: I am going to spend more than 5K to get a new engine put in the Comanche. But for around 10K, I could find a first generation Toyota Tundra Access Cab with a 4.7 V8, maybe 4x4 also. The Access Cab will give me an upgraded cab interior with more room than the Comanche can ever have. I would still have a 6 foot bed (down sized from the Long Bed Comanche). Towing capacity for the Tundra is 7K+, compared to 5K with the Comanche. Most important, I would be trading Jeep quality for Toyota quality. (Think Jeep electrical issues, then think about Toyota electrical issues). Gas consumption is a wash. Besides, I only used the truck for under 5000 miles a year, so fuel is not big expense - it is just part of the cost to have a truck around the house. The down side is simply that I am buying a used truck that somebody else doesn't want. I really don't know the service history of any used car or truck I buy. With the Comanche, I have 8+ years of personal history/knowledge with the truck. What am I missing? Anyone want to share their thoughts? So is there something I am not thinking about?

The muffler shop will fix the exhaust manifold for $280 including labor and I pick it up on Monday. Not worth 4 to 6 hours of my time right now. We are right in the middle of a kitchen renovation. Next, I will need a new oxygen sensor. Amazon lists these as fitting the 91 Comanche 4.0: http://www.amazon.com/s/ref=sx_as?rh=n%3A15684181%2Cn%3A!15690151%2Cn%3A15719731%2Cn%3A15730551%2Cn%3A15730891&qid=1458504689&vehicle=1991-42-348-20----7-3330------1-1 Any one with some experience on these? Also, good tip on larger fuel injection units, thanks, New headers will come when the current 4.0 gets replaced with a stroker. Same thing with the flex tube in the exhaust.

Found a hole in the stock header that had been repaired by a previous owner near the collector. New factory header kit is $400 and 4 hours labor. May or may not solve the problem. Going to take the truck to a muffler shop tomorrow an see about patching the hole on the cheap. Truck is a 91 4.0 new header has to be CARB complaint.

Highway driving with a 5 speed? The 3.55 gearing. Automatic? 4.10 AMC 20. But even with the 5 speed, the 4.10 could work very well. Especially to tow something every now and then. Me, buy them both and decide which one later. What are you running now and why are you looking to change?

Lets remember what is really important here: Nobody got seriously hurt. The cars/trucks are just metal. You buy another car/truck and everybody moves on with their life.

Stay with the 215/75 x 15 tires. Keep the tire pressure up. Hold your speed down to 60/65. You will get the best mpg that way.

Don, Have you given any thought to changing over to OBD2 engine management? Thinking possibly that would allow different/"better" tuning for city mpg and for more power if requested.

It would be very good for future reference, if you would post a full set of pictures. Both before and after installation. I would also like to see pictures of the welding before you put paint on the welds. Also, what was the freight cost delivered to your place?

Don, Any idea where your timing curve is when your are doing city driving? I "assume" for highway driving you timing is well advanced. Not sure it is the same with city driving. Know the total spark advance can be a big help for highway mpg.

As I recall the Isusu Rodeo/Honda Passport axel is 1 inch narrower than the Comanche. It also has 6 wheel bolts and factory disk brakes. The automatic V6 versions had the 4.10 axle and the manual trans V6 had a 4.30 axle. I used to own one of each.

You have discovered one of the "benefits" of global sourcing. Companies will do what they need to do to make a buck in the name of efficiency. There is an old Latin saying - Let the buyer beware.

My so called city driving still includes a lot of freeway driving - even if in a few miles of stop and go morning rush hour traffic. If I were doing a more city street stop and go driving I could easily see 14 mpg as a regular item. Also, short trip driving doesn't give the car time to warm up. Don - aren't you doing a lot of short trip driving these days? That also kills the mpg.

It is a 1990, the ad is wrong, per the seller. I am in contact with the seller and will post what I learn.

The issue is mounting 95 and later seats in the 94 and earlier Cherokee or Comanche. You don't have to resort to welding. I took the bucket seat brackets off my Comanche buckets. Then bolted the seat brackets to the floor of the MJ. Next I used 2 pieces of 1.25 wide by 18 inch long flat stock to connect each of the 2 seat brackets. Drilled a hole in each end, used a 1/4 20 bolt to blolt the flat stock between the two seat brackets. Next, on the donor 95+ seats, I cut off the brackets that mounted the seats to floor. That left me with just the sliders attached to the seats. Then I cut 2 more pieces of flat stock about 11 or 12 inches long and bolted them across the seat sliders. After that all I had to do was fit where I wanted the new seats on the flat stock between the old Comanche seat brackets. Drill 4 more bolt holes, bolt the seats down and they work just like they are supposed to. No welding, just 4 pieces of flat stock and some bolts. I did spend quite a bit of time adjusting the seat position before I bolted everything together. The end result for me is a set of Grand Cherokee seats that fit great in my Comanche and no welding or cutting to the Comanche floor. It is a completely reversible modification.

For the last 3 months, the Comanche has been my daily driver while my 96 Passat is in the paint shop for a full repaint. It has been quite a difference in fuel costs, going from the 40 to 45 mpg with the TDI to the 15-18 mpg with the Comanche. Because I have been making a weekly freeway trip of about 150 miles on each tank full for the last few weeks I thought it would be of interest to see what happens to my MPG if I slowed down from my normal 75+ to a more reasonable 60+. With the last 75+ tank, I traveled 395 miles on 22.25 gallons for an average of 17.75 mpg This tank at 60+ I traveled 434 miles on just about the same 22.34 gallons for an average of 19.42 mpg So by just slowing down my max speed, the mpg went up by 9.44% My truck is a 91 long bed with a 4.0 and AW4 transmission 2 wheel drive. Tires are Kumho 225/75 x 15.

Glad to see this issue resolve. One way or another. Best wishes to both of you. Life is way too short to let crap bother any of us for very long.

Needs more than a Micro-Bed. Diesel is good but how much torque? What Transmission?

Sad to hear. Best wishes to the family.

Glass is the same - i "THINK" Buy the doors from an xj that is the same color as your doors and has power windows. Get all the electrical wiring along with the doors. That includes the cross body harness. Swap the doors, connect the cross body harness (That is the hard part). If you can find a 2 door XJ with power windows, then get the power window /locks control from the drivers door. Use that in your driver door and it will look just like factory. If you can not get the cross body harness - you can make one by your self. Don has posted a diagram/how to several times. Me? I just paid an auto electrician in Tijuana to hook them all up.

Check the crank casting number! It is the ONLY way to be sure. Or buy a 258 engine - even then you have to check the crank to be sure it is a 258 and not a 232 or 199. Check the crank!

Yes, not a Comanche shell. But the dual handles on the rear window are a nice feature. If you can identify which truck the shell is for, you should be able to sell it for $100 anyway. That factory bed liner is good quality, Mine is still OK after 25 years.

Power windows will not solve your problem if your windows currently do not go down all the way. You need to identify and solve that problem first. There are a number of threads about adding power windows to the Comanche, A simple search will bring up a number of them. Best thing for you to do is either search the internet for an add on power window kit for the 2 door Cherokee XJ or to find a Cherokee with power windows and salvage the parts from that truck. Several of us have done this, but it does take some electrical knowledge.

YXMJ, Don is absolutely correct about the value and the NEED for actual dyno tests to document results of changes to the engine. While I have not built a Jeep stroker, I have gone down this path with my VW TDI engine. The stock VW 90 hp TDI engine puts out about 78 hp at the front wheels. Over the years of modifiying my engine I have run more 2 dozen different dyno tests to prove out the results of different modifications. My current tune on the TDI puts down 162 hp and 285 lb/ft at the front wheels. And at that I dialed back the tune from 173 hp and 313 lb/ft to reduce smoke and to keep the clutch from slipping. My plan for spring includes pushing the boost up another 6 lbs (32 psi) and adding more fuel. Dialing in the extra boost and the required amount of fuel will require about 8 or 9 more runs on the dyno, but we will be sure to document the results. From there, I have a ported/polished head to test for power improvements. Without all the dyno testing, I will have no data to validate the value of the ported head. Last summer, I participated in some cam dyno tests. The dyno showed no measurable gains in spite of the claims from people who purchased different cams and only used their "butt dynos".

Any suggestions for what will be nice and quiet in a replacement muffler? My stock exhaust is suffering with some leaks. So it is time to replace it from stem to stern (perhaps the headers also).

You really do need to think about how much towing you are going to do. If hauling trash to the dump once a year, then just use third and fourth gears with your present set up and keep your speeds down below 55 mph. If you are going to want to tow 5000 lbs a 1000 miles every month, get something else. My Comanche come from the factory with all the options to "properly" tow 5000 lbs. Automatic, Long Bed Dana 44, Metric ton/Big Ton package, all the H.D. factory stuff, frame mounted hitch, I added an equalizing hitch to complete the package. The Gross Combined Vehicle Weight for my truck is about 9500 lbs. But it is not something I want to use for regular towing of 5000 lbs. On the other hand, it works just fine to haul crap to the dump and even to move a full trailer of household stuff 3-400 miles, once in a while. But if you want to improve your Comanche for towing, get a 4.10 rear end and put some disk brakes on the rear. Buy a frame mounted hitch, Your bumper mounts are the weak spot, that is why you want the frame mounted hitch. Remember, when you are towing, brakes are REALLY important, so is leaving way more room from other cars on the road. It is no fun when you are trying to stop quickly and you have 4500 lbs behind you pushing you down the hill. Never mind a long down grade on the interstates.