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May 2011 Your Jeep

Posted in How To on May 1, 2011
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Cellular Service
I have a '95 YJ with a 2.5L engine and would like to mount a fuel cell in the rear. I would like to know the ins and outs of the installation. What do I use for the fuel pump and the plumbing? What stock parts should be used? I would appreciate any info and advice!
Bob Payne
Via email

If you're using a generic fuel cell, Contact Hesco (205/251-1472, The company sells both internal and external fuel pump assemblies that you can use with a fuel cell or stock Jeep fuel tank and will give you the proper pressure to run your 2.5L. The company lists a bunch of different fuel pump types and styles on its web site if you want to check them out before you call.

Or, GenRight Off Road (805/584-8635, offers a 23-gallon fuel cell under PN BST4000 that will accept a YJ in-tank pump assembly with some modifications. Or, if you don't mind purchasing a TJ in-tank pump assembly, you can use the company's PN BST2100 fuel cell. This 20-gallon model is designed to directly accept '97-'10 Wrangler fuel pump modules. Trasborg says the TJ pump is a way better pump to use if you are gonna wheel at angles. It holds over a quart of fuel inside the pump pickup housing so even if the pickup is uncovered for a bit the Jeep won't starve. It's the same ohm range for the fuel gauge as '91-up Jeeps.

I have always been a fan of Super Swamper tires, namely the LTBs for their wrap around rocks. I recently came across a forum posting about Simex Tires. These tires appear to insanely mud-capable. Why have I not heard of these tires in the mainstream for use in mud? Do you know anything about them such as DOT legality, distributors that carry them, cost, and mostly if they are up to par or exceed Swamper capabilities? Have you ever tested these tires?
Nick Sekulich
Cool, CA

I ran into Simex Tyres back in 2000 or 2001 when I was on a month-long assignment for 4WOR and Four Wheeler magazines over in Australia. I got to watch them in action in a variety of gnarly terrain from rock to dirt to deep mud. They look impressive, but judging from the performance I witnessed I'd say you're not missing anything by running your Swampers.

I checked back then about getting a set in the USA and at the time they weren't DOT-compliant. Not that they're unsafe, just that the Simex corporation wasn't selling them in the USA, so they hadn't gone through the hassle and expense of getting the DOT certification.

As for Simex versus Swamper, the Simex tires are better suited to street driving than an LTB or regular Swamper, but didn't seem as flexible or grippy off-road. For our use here in the states, I believe the Swamper is the better off-road tire.

I currently have an '83 CJ and am looking to buy an '86 CJ for some donor parts. I was curious to know what transmission came in the '86 with a four-cylinder? And do all '86 CJs come with the Dana 44 rear? What should I expect up front?
Robert Collins
Satsuma, AL

The transmission in the '86 four-cylinder is going to be a Borg Warner T-4. Tranny ratios are: 1) 4.03:1; 2) 2.37:1; 3) 1.50:1; 4) 1.00:1; R) 3.76:1

Popular convention holds that only the later '86 CJ-7s got the Dana 44, but every factory '86 I've seen (four or six cylinder) had the Dana 44 rear axle. However Trasborg says he's seen 'em with Model 20 rears. I guess we're saying don't count on it being a Dana 44. The Dana 44 rear should have 10x1.75-inch rear drums and either 3.54 or 4.09 gears. The front axle will be a wide-track Dana 30 with 12-inch disc brakes and similar gearing.

I have had an interest in Jeeps for quite a while. I don't, however, have the need to go off-roading except for on occasion. I have decided to purchase a '97 to '02 model year Wrangler with the old 2.5L pushrod I-4. In your own opinion, is this a good choice? I don't intend to lift the vehicle; I only want to customize it cosmetically. The only thing that I would like to do is maybe add the six-speed tranny for slightly better gas range. Is there any conversion your magazine is aware of, and is there anything to be looking for in an older model year?
Anthony Cioffi
Marshalls Creek, PA

The 2.5L TJ is going to be less expensive to purchase. A lift and larger tires really saps the performance, so it's a good thing you're willing to keep the tire size small. A factory five-speed TJ will have an AX5 transmission, NP231 T-case with a 21-spline input, a Dana 30 front, and a Dana 35 rear. The axle ratio is 4.10.

You can use tires up to 31x10.50, but a slightly smaller set of 235/75-15 or even 225/75-15 will deliver the best mileage and on-road drivability.

I would strongly advise against expending any effort into swapping the NSG-370 six-speed manual due to its complexity, expense, and limited performance gains. Besides, without custom-built parts it's not even possible as of this time. The costs would negate any fuel mileage benefits for over a decade and the drivability boost really wouldn't be anything to brag about. You're really better off sticking with the AX5 that comes with the Jeep. Besides, there's no real easy way to put the six-speed behind the 2.5L because the 2.5L engine's bellhousing bolt pattern is the same as a 60-degree GM. On the other hand, the integral bellhousing bolt pattern of the six-speed is 90-degree Jeep/AMC. If the AX5 scares you, Advance Adapters make conversion kits to mate the AX15 five-speed from a 4.0L Jeep behind the 2.5L using the factory AX5 bellhousing. Check our web site at for the story, "Five-speed for Four-banger."

I'd stick with the stock AX5 five-speed and if it ever gives you trouble, look into swapping in the heavier AX15 as an upgrade. You asked about tips on purchasing a Jeep, but I'm a bit of a masochist. I like them bare-bones with the fewest possible things to worry about or go wrong. In the past I've had Jeeps with nicely upgraded interiors, bells, whistles, and so on. It just made me worry more. My current Wrangler has no carpet, stereo, or frills. I can let the kids spill juice all over and then clean it with a garden hose. I'm not saying you shouldn't make your Jeep nice (or even run without a stereo). That's just where my head is at. There's also a slight performance and mileage boost from not running a heavy hard top, full metal doors, a carpet and padding, and so on.

Just some things to consider:
•Some 2.5L Jeeps came without power steering, so check that yours has it if you want it.
•Most 2.5L Jeeps don't have A/C, so if you want that be prepared to look.
•Don't buy an automatic transmission with the 2.5L. They get worse fuel mileage than the 4.0L Jeeps and they're painfully-underpowered since an auto tranny takes about 20-40hp to spin.
•Hard tops and full steel doors with roll-up windows fetch more money but limit your summertime fun. Running a Jeep with no doors is one of the cool parts of owning these vehicles.
•2.5L engines can run in excess of 200K miles with few troubles. Pull the oil-fill cap and check for excessive carbon build up on the bottom of it to easily gauge the condition of the motor. More carbon means more blow-by and ring wear.
•Most factory TJ radiators develop leaks where the plastic tank ends are crimped to the radiator core.
•The '97 model year has an inferior cowl vent design that lets rainwater pool on the passenger-side floor. The '98-up Jeeps fixed this problem-kinda.

Crack-Pipe Dreams
(The following is an excerpt from a hypothetical bench-racing session between some industry buddies. If anybody actually builds this, please let me know at!)

Somehow, we gotta do the Viper V-10 in a Jeep. The big question is not how to get the motor or the Jeep, but what should it be like? Rockcrawler-not. Mud-racer-maybe. Wheelstander-oh yeah!

How about it? A backwards-mounted, mid-engine SRT10 motor in a TJ or JK with a transfer case under the hood and mega-paddles in the back goin' to Glamis!
Jim McGean
Huntington Beach, CA

Ha! We'll use your LJ, but you can't stop at just bolting in the engine. You've got to go whole hawg-crazy and stuff quad turbos on it. Your goal should be 1,400hp minimum, but 2,000hp is more likely.

Since the aftermarket VGT systems are still a bit unreliable, I'd do a set of twins on each manifold-the small one for low-velocity boost and the bigger one to take over at higher rpms. That sucker would make 1,500lb-ft off idle and probably upwards of 1,400hp on pump gas. More on race gas. You'd need a billet crank, chromoly rods, forged pistons, hogged out aluminum Viper heads, ARP studs, and some killer head gaskets or an O-ringed block, but it's all doable.

I think in this economy if you're gonna do something a little outrageous, it may as well be completely outrageous. I think the middle ground is going away-you're either eating soup from a can or caviar from the bellybutton of a supermodel.

Hava Seat
Every year I see a comparison article on tires. Last year I read one on tire carriers. And there have been other comparison articles that I can't think of off the top of my head. However, I have never seen an article on seats for your heap.

I am looking at MasterCraft, Beard, PRP, Corbeau, and other manufactures, but I don't know what's the best for my back. What will hold me in the seat the best in order to give me the ability to drive by the seat of my pants? What dries off the quickest? What holds up to mud? What lets me easily get in and out of my lifted Jeep, etc.?

Additionally, why would I want a fixed over a reclining seat? Why do I want suspension over foam? Why do I want cloth over vinyl/cloth combo or waterproof neoprene, why, why, why?

So, any help that you can provide would be great, and if you could write an article, that would be grand.
Chip Justice
Lovejoy, CT

It may be a story we'd consider doing in the future, but for now I've had enough aftermarket seats and I think I can help you out.

MasterCraft-Just about the best out there. The color stays put, they're comfortable, provide good support, and have nice side bolsters without being too difficult on ingress/egress. They bolt to YJ/late CJ seat frames. Rubicons are a bit wider and slightly larger on the outside, while the Sports are slightly more snug and a little more compact. I have thousands of miles in Rubicons, and I've run the Sports in my Flattie for years. The reclining Baja RS buckets are also really good. I ran them in my TJ, but unless you do a lot of long trips where the passenger needs to lie back, I'd say the money isn't worth it and the regular Sports or Rubicons are more comfortable.

Beard-A very, very close second to MasterCraft and same quality as far as fading goes. Most models seem geared more towards off road performance, so they hug more snugly and have larger side-bolsters. The mounting tabs are vertical, not horizontal, so you'll need the adapters if you're mounting in a YJ or late CJ.

Corbeau-The old fabric faded really fast. The black ones I put in my M-715 already looked purple after a couple trips off-road and the material isn't as durable as the Beard or MasterCraft. The new replacement fabrics seem more resistant to fading, but the wear patterns still showed up more quickly than more expensive seats. They are more affordable, though, and really comfy and supportive-so if you have a top or go with the vinyl instead of fabric they can be a good choice. The mounting tabs are vertical like the Beards.

Smittybilt-I've had the Sport-style reclining buckets, not the suspension seats. They were firm but not uncomfortable at all. The side bolsters are sort of big, but you can still get in and out easily. They had good overall quality and I was pleasantly surprised considering the very attractive price. They have YJ/CJ-type mounts.

Bestop Trailmax-Very comfy and good material quality. I remember the Black Denim fabric fading to a light purple on the ones in my '95 YJ, so I'd say the vinyl ones would probably be better if you're putting them in an open-top Jeep. They fit well, the mechanisms worked nicely, and they were good for long hauls. They have YJ/CJ-style mounts.

Bestop Low Backs-Had these in our Project Hatari! CJ-6 as early CJ replacement seats. They were a big, big improvement over the original ones, but the top of the seat frame would dig into my back. The bottom cushion was nice, supportive, and comfortable. The material (full vinyl) did very well in the sun with no fading or staining. They have YJ/CJ-type mounts.

Corbeau Sport type seats-I had these (type like the Bestop Trail Max or Smittybilt Sports) in my '85 4Runner. They were horrible. The material was fine (full vinyl), but the seats were rock hard and uncomfortable as hell. They had CJ/YJ-style mounts.

PRP Daily-Driver-While I haven't actually owned a pair of these, a lot of my friends run them and I've spent a good deal of time sitting in them. The fabric wears well and has good resistance to fading over the long-haul. They're also very comfortable and offer good support. Like the MasterCraft Rubicon seats, the side bolsters are doable for a daily-driven vehicle and they seem to offer a bit more room when seated like a Rubicon-model seat. The price-point is an attractive feature.

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