Hello, I just bought a 1997 Jeep XJ from Pick and Pull builder section. Normally, I don't even give these cars a second glance, but this Cherokee looked really good and so I made a stupid low ball offer and ended up with it. She is a Country Edition PJN, NP242, 8.25, camel interior, captain chairs, tow package. She has 275K miles .......so stupid high miles, BUT .........to my total surprise and utter astonishment, no issues. The gauges all work, it doesn't over heat, fluids are clean, no lights on the dash, suspension is solid, ac works, fans kick on ......also has the original radio .........yeah, the original radio ..........and even more crazy, the original headliner .......so super weird. My guess is that it was owned by an older couple, who probably turned it into a dealer who then in turn dumped it at P&P. So going to be going through it over the next couple of weeks and getting it prepped as a daily commuter...........the question I have is: What is a good rim/tire combo I can put on here? The wheels I have now are 225/70/15 and I am looking to downgrade, but without looking totally stupid. I need much lighter smaller wheels to save on gas and increase acceleration. This will be a city commuter ...no lift, no trails. I really like the lace wheels on the older ZJ and XJ's which are 15's. So thinking of staying on 15's but reducing the wall size..... I am not really looking to keep the same stock ratio wheel size, although if do find a pair of 16" dark grey icons, I would . So can anyone recommend some non goofy tires specs that will work with my needs?

My new commuter XJ.

 

235/75/15 would be the size I would run. Better selection of tires and good prices on them. They are not much different then the 225/70/15 you have now. The state/area you are in may affect what tires you want to run depending on the weather conditions.

 

I need a daily.....a sole street Jeep. It will never see a trail. I am trying to decide between 215/65/15 and 205/60/15. These are the tire sizes I am leaning toward. I want to reduce the rotational weight as much as possible without sacrificing aesthetics. Big tires kill gas mileage and just make the Jeep sluggish and less responsive. Anyone have pics with the aforementioned tires sizes on their Jeep ?

 

Thanks FB Marketplace........


My choices for my new commuter .....

 

This sounds like a silly concept but I'm curious how this plays out. What kind of mpg gains are you anticipating/ hoping for by going with smaller tires and less rotational mass?

 

Well apparently Chrysler didn't think it was so silly when they rolled out the "Sport" trim which saw a 1 mpg improvement in fuel efficiency over other similar trims........and those in some cases came with 215/65/16 tires. So they took tire size into account on some level. Honestly though, I plan on taking additional steps to achieve my goal of lower fuel consumption which should have a significant cumulative effect.....tires are a big part of it though. I haven't dug too deep into into it as of yet, and plan on reading some threads on the subject of increasing mpg in an XJ, but I can readily point to weight reduction, 12 hole injectors, and cleaned/bored out throttle body as some obvious leads. The things I won't be doing to this Jeep is putting on stupid pieces of hunks of metal that don't do anything for me.....like metal bumpers, rock rails, winches, ridiculous fat tires, lame suspension components that cause all sorts of drivability problems.....and worse offender of all ......big fat heavy 12" woofer boxes. Oh and how can I forget the scourge of all mpg killing factors .....the full size spare tire stuck to the side of my Jeep. GONE! I have Triple A+ for God's sake! I am staying clear of all that stuff. This is going to be my winter daily!

 

[\Quote] Honestly though, I plan on taking additional steps to achieve my goal of lower fuel consumption which should have a significant cumulative effect.....tires are a big part of it though. I haven't dug too deep into into it as of yet, and plan on reading some threads on the subject of increasing mpg in an XJ, but I can readily point to weight reduction, 12 hole injectors, and cleaned/bored out throttle body as some obvious leads. [/QUOTE]

Here's a link for you that might get your rolling in a definitive direction:

https://www.motortrend.com/how-to/15...ing-true-lies/

I would highly suggest you don't just jump on a claim train for results when it comes to this stuff. This forum is already filled with enough miss information based on false claims. Thorough explanation of what your doing and the results it has or has not made would be beneficial.

If you dig around regarding the fuel injectors your gonna see a lot of claims but really a brand new set of factory injectors will do the job of imporved performance over the potentially troublesome "upgraded X hole injectors"

 

Good find! Unfortunately the 4.0 design and the brick like body shape don't make these great MPG vehicles and you are pretty much stuck with those major limiting factors. If you really want good mileage fix this up a bit, sell it and buy a little Honda.

Assuming you have a sound ignition system with properly gapped plugs and an engine in decent mechanical condition, some things to consider to improve MPG:

Stay with the wheel & tire size on the door frame sticker or specified on base models such as Sport. Tire manufacture & design does make a bit of difference in gas mileage. Look on the Tire Rack web site for highway tires. For tires you are considering look at test results or Specs section for those with lower rolling resistance. Once you have new tires keep them inflated at the high end of the recommended pressure for your application.

Good lubrication helps some. One easy mileage improvement is to run a high quality synthetic 5W-30 oil in the engine. I would run new oil a couple thousand miles and change again as the detergents in new oil will help clean out some internal buildup. Other than cleaning the throttle body and making sure there are no vacuum leaks I would not mess with the throttle body. Most of those mods get you zero or little gain and not worth the cost and effort. Maybe change front and rear differential fluid with fresh 75W-90 synthetic gear lube.

I am sure the under engine splash shield (its a rubber type material) is missing. Adding one may help with air flow under the engine area and improve aerodynamic efficiency a bit. It also helps keep water out of the alternator and maintain proper air flow through the radiator.

Check that the radiator cooling fan mechanical clutch is working as it should. If always engaged, at highway speed it will consume unnecessary HP and be more noisy.

Drive with windows up

All these are small potential improvements but together they can add up to a small increase in MPG.

 

That is a hell of a score. Nice job!

 

I have been around XJ's for a long time (1984-2001 model years, I have owned the first and the last years and 5 in between) and I don't recall seeing a year that they came from the factory with 16" rims/tires. If you use a tire other then the diameter of the tire size that is on the sticker inside the driver's door your speedometer will be off as will your mileage. Go online and find the diameter of a original tire and whatever you want to compare it to. It will give you the answers. Just remember if you get a wider tire it will lower your mpg as it is a larger footprint and that is more friction. In the end, the way you drive will affect your mileage more then anything else. Slow acceleration to moderate speeds and holding a steady speed will help. Having any mechanical problems, injector clogging, fuel line leaks, O2 sensor, dirty throttle body, etc going bad will drop the bottom out of your mpg.

BTW, you got a deal on the XJ!

Good Luck!

 

Well, Yes and No. I didn't actually show the passenger side .....lol. It was involved in fender bender so it sustained some damage. So the mirror, fender, front fender support bracket, fender flare brackets, fender flare, and bumper were wiped out......miraculously in all the damage it sustained, the header was untouched. Go figure .... regardless it was a super turn-off to look at......I was like, I am not touching the body until I make sure it's mechanically sound .......that lasted a couple hours before I went crazy and started looking for body parts ........



Fixing the damage was pretty easy but super annoying! The hardest part was tracking down all these stupid parts which had interchangeable part numbers.....the fender flare brackets being the most notorious. A billion bracket combination exist...it's so weird, they are all virtually the same and then BAM! hole and stud in the wrong place. Oh and forget about getting them out without breaking the studs.

Fender removed......luckily there was no frame frame or attachment point damage. That was my worse fear. Even the flimsy lateral support bracket underneath the splash shield was undamaged.



Offending parts removed .......I really didn't need to remove the bumper, but it did have a crease in it which annoyed me and the front support bracket was slightly bent which annoyed me too. The problem with removing the bumper is the rivet that holds the bottom deflector to the bumper. That was just the lamest possible way to fasten those two parts together...pretty much guaranteed not to come off easily if you want to remove the bumper



I love e-commerce ........likelihood of finding all the parts that I needed, 100%. Quadratec really came through for me, it had the little flange nuts that hold the flare brackets to the fender .....I basically broke all of those trying to get the brackets off the fender.......now I copper greased the crap out of all hardware so it will never do that to me again.




So yeah, I just got done with this fix. I am still waiting for the passenger side mirror to arrive. The ebay guy I ordered it from delayed shipping forever so it's coming late .....I should get it in by Friday. It's super important b/c buying this car from a junkyard has it's problems.....namely I need to get it retitled or something like that to get it on the road ....which means it has to get inspected by the police. I have to have everything in it's proper place. All in all, I am happy with it.....I knew the damage wasn't something I couldn't handle and realistically I spend more money taking my family out each weekend then I did on this car. I think the biggest setback to someone picking up this Jeep was the high mileage and the lack of Title. Additionally, it didn't have a passenger side window (more on that later) .....so it was left open and the inside was starting to mold. The junkyard was in a hurry to get rid of it .......

 

Certainly 60th Anniversaries had 16's & some other 2000-up models because both Icons & SilverStars (I think) were offered.

For a little insight into wheel size/gas mileage: my '98 on 31x10.5's is 2 mpg worse than my '99 on 235/70's but running it on 265/70's during the Winter made no noticeable difference. On that basis, to improve mileage by 2mpg you'd have to come down maybe 4 sizes but the smallest tyre fitted to XJ's was a 215/70 & I would've thought a 205/70 as the smallest you could realistically fit on a stock 7" rim.

Just can't help wondering how much gas you will have to save to pay for the replacement wheels & tyres

 

Yeah for sure the Limited trim came with 16"s.

I think I should clarify that I am not super preoccupied with gas mileage.... MPG is just one of those things I would like to alter to my benefit, but it's not super crucial.....realistically I am more concerned with nimbleness' and agility when it comes to this Jeep and MPG is just one of the side benefits. I am looking to be quick off the line and to be able to accelerate at a decent rate on the on-ramp......as quick as an XJ allows for of course. Additionally, I am looking for a nice smooth ride.....something that a stock suspension and steel wheels provide. I also don't want to go too thin on the tires b/c of aesthetics and comfort, so I am trying to find the best middle ground. I have a 2021 Prius all wheel drive that gets 55 mpg I am not by any means hurting for MPG vehicles. We recently had a winter snow storm here in Portland and my Prius was kicking butt and not taking names......nothing can compete with an awd Prius.

 

So progress on this project has been painfully slow .......apparently everyone and their mother is after XJs these days......at least in my area. It's kind of stupid b/c all they do is trash them anyway, but anyhow, I was finally able to find a PJN Jeep and took the doors which I needed to finish the last of my body damage. Here is a protip .....never ever ever ever try to remove Cherokee doors from the hinges without proper tools. I thought it would be an easy peasy job, but instead I had to go to Homedepot and buy a sawzall to cut the hinges off and get my doors. Apparently clearance is an issue when trying to remove the doors from their hinges and it's very difficult to get the proper torque on the bit. Luckily, I learned this on a scrap yard Jeep and not on my project Jeep. I would have been hosed....but I got the doors off and the transplant went well. I was very nervous when I took my doors off despite buying a special low profile ratchet/bit wrench. I transferred all the internals and seals and everything works as it should. I am still waiting for the pin stripping tape to make things just right........


This thing was only in the yard for 2 days and it was complete .......

I also had a problem with my air bag light being on ......since I have to have this car inspected by DOT to get it back on the road I had to fix the light. I went after the clock spring and that was a total fail b/c the clock spring was fine .......it ended up being the air bag module under the console. Huge time suck .......however, I did take the opportunity to reinforce the console when I took it off by buying that metal bracket and throwing out the broken plastic one. I was a little apprehensive b/c some people reported that it wasn't lining up just right .....however, mine did. Not really sure, but I think some people are having problems with these because they try to install them without completely removing the console and seats.....doing so made it super easy to install and align this bracket.

So finally fired her up again only to find out that the damn radio didn't work ......so ......not only did the main display not light up, but the CD player was broken and the tape deck destroyed my tape. I could only hear the radio ..........I removed the SOB. So now I have to find a new one .....so I am going to hit the junkyard .....caravans, rams and dakotas watch out! EBAY wants too much money for these........for what they are.

Factory CD/Radio player

In the meantime, I decided to install a new radio while I find # P04704383AH. I did a pro install ......I made sure not to cut the harness (it made it this long right), bought an adapter and put in a radio that fit right in without any sort of modification. Even the factory screw holes lined right up.

Pretty lights!

So this is where I left off ........I am pretty much done with the interior, but not really. I think I am going to focus more on engine work now, starting with coolant flush, oil change, filter, plugs, cap, rotor and cleaning the throttle body for starters..........and maybe the wire upgrade too.

 

Congrats, you are making great progress!