Eagle

Technically, there ain't no such critter as valve "seals." The valves are fitted with little rubber/plastic unbrellas whose purpose is to direct as much oil as possible dripping off the valve cover away from the valve stems, but the umbrellas go up and down with the valves and don't seal anything. The are more correctly called "deflectors." Fouled plugs are much more likely to be caused by ring problems.

Here's the 88-90 4.0L coolant system bottle, from the Quadratec web site: http://www.quadratec.com/products/51216_01.htm As noted, this is not an "overflow" bottle. It is an integral part of the pressurized cooling system. It will not function properly without a cap, and the cap has to maintain pressure. That's why it's generally useless to replace only the cap -- a new cap usually won't seal on an old bottle. Just buy the whole assembly. It should not be filled all the way. It should be half full when the system is cold. NEVER remove the cap when the system is hot.

As noted, you can't knurl valve seats. But I also don't know how you would install new valve guides, since they are an integral part of the head. That notwithstanding, if you were losing compression through the valves you would either have air being blown back through the intake, or out the exhaust. Leakage at the valves would not pressurize the crankcase. It sounds like your rings are not seated. It could be that the rebuilder didn't fit them right, didn't use the correct rings, or didn't hone the cylinder walls correctly. It's also possible that he honed the bores too much, and used the original pistons so that they are now a sloppy fit in the bores. Another possibility is that he used chrome rings, which are very hard, take forever to seat (and never really seat well), and require a different hone pattern. Even then, they often always use more oil than regular rings.

I'm sorry, but you are incorrect. Ohio may consider the Comanche a variant of the XJ, but Jeep did not and the VIN does not in any way indicate so. The VIN decodes as follows: Digit: . . . . . . . . Means ------------------------ 1st . . . . . . . . . . Country of manufacture 2nd . . . . . . . . . Company make (Jeep) 3rd . . . . . . . . . . Type (Truck) 4th . . . . . . . . . . Engine Type 5th . . . . . . . . . . Transmission 6th & 7th . . . . . . Series (65 = 4WD Comanche, 66 = 2WD Comanche) 8th . . . . . . . . . . Trim Package 9th . . . . . . . . . . Check Digit 10th . . . . . . . . . Model Year (G=1986, ...) 11th . . . . . . . . . Plant of Manufacture (T= Toledo) 12 - 17 . . . . . . . Serial Number There is nothing in this code to suggest or mention XJ. The XJ VIN shows Type 'C' for the third digit, which translates to "Multi-Purpose Vehicle" (not "Truck")

Guys, he's asking about a 1988 Wagoneer. That's an XJ Wagoneer -- a Cherokee in dress-up clothing. The rear axle just needs to have the spring perches cut off and relocated. You can leave the XJ shock mounts in place, or cut them off. They're not used in the MJ. The ratio will be 3.54 if it's a 4.0L, and either 3.73 or 4.10 if it's a 2.5L. The Wagoneer wasn't available with a standard tranny, so there's no chance of 3.08s. Although the XJ Wagoneer didn't have a Dana 44 front, and the question was in the plural. Are we talking "Wagoneer," or "Grand Wagoneer"?

Before you do ANYTHING -- (1) look at some other XJs; (2) measure from the center of the axle/hub/hubcap up to the bottom edge of the flare and post the measurement; (3) take a picture of your springs and post the picture. ALL XJ springs have essentially negative arch. It's a spring-over-axle suspension. Although nominally the spring isflat, in fact the forward part has a VERY slight positive arch and the rear part has a distinct negative arch. More than likely your problem is just the missing bump stops. If in fact the springs have sagged significantly, you cannot re-arch them in the vehicle. A spring shop could do it, but you'd be better off using that money to buy a set of rear springs from a junkyard, disassemble them, cut the eyes off the main leaves and use them as add-a-leaves.

It's normal. If the clutch were slipping, your RPMs would increase and you wouldn't have to shift.

I am currently running 31x10.50R15s on factory rims on my '88 Cherokee with no lift. The MJ has a lot better clearance in the rear, so it should be no problem. There is slight rubbing of the front tire shoulder on the lower control arm at full steering lock. Takes about a day to get used to how far you can (or can't) turn the steering wheel. And a 2" budget boost will NOT alleviate that anyway.

With 4.88 gears and 32" tires, 70 MPH will be 2714 RPM. With 4.88 gears and 33" tires, 70 MPH will be 2619 RPM. The engine has a 5,000 RPM redline, but in overdrive with big tires, pushing a "brick on wheels" down the road, it's extremely unlikely you could actually get it up to the redline in top gear. But you should have enough moxie to get up over 100 MPH -- which IMHO is a helluva lot faster than anyone should be going in a 20+ year old Jeep that's lifted and riding on mud tires.

Just saw a reference a day or so to a state (NJ?) that calls it the CMV (Commission of Motior Vehicles). Connecticut uses DMV.

Bummer. They make torque wrenches and the manuals publish torque specs for a reason, but it doesn't help if the guy doing the work doesn't bother to follow the specs. If some of those bolts were only finger tight, it may be a hidden blessing that it didn't work, because you could have been driving around with a hand grenade under your feet.

FWIW, 31x10.50s with 3.73 gears turn EXACTLY the same RPMs in 5th gear as a stock XJ or MJ on stock tires with the 3.55 gears. That's a decent combination for street use and light trail use, but not really enough gear for moderate to serious off-road use. IMHO, "ideal" ratios would be 3.73 for 30" tires (which was the plan when I bought the 3.73 gears), 4.10s with 31s, 4.56s with 32" tires, and 4.88 gears for anything larger than 32".

Three soldiers two bunkers away from me in Vietnam were killed by NVA infiltrators because the guy who was supposed to be awake and on watch was high on Mary Jane. Don't EVER try to tell me weed hasn't ever killed anybody.

:sigh: Yet another incomplete poll. Whatever happened to "No opinion" or "Undecided"?

The reference to tubes being corroded through leads me to believe the original poster is not really talking about the sending unit. I think he's talking about the fuel pump mounting assembly, with the two tubes and the mounting flange.

Where did you see rust on the bed? There were no pictures of the bed, and it seemed to have a bed liner. Did you mean the upper part of the quarter panel?

My guess is that the radiator isn't doing anything.

Jeff, I switched the '88 XJ from 10W40 dino oil to 20W50 synthetic at about 180,000 miles for the same reason. Mine wasn't quite as low as yours when warm, but when new it ran 50+ psi at highway cruise, so the decline was obvious. The change to 20W50 brought it back up to 40-45 psi highway, and it has stayed there for several years and over 100,000 miles. (I'm now at 282,000). But we get pretty cold nights here in winter, so when I discovered that Castrol has a 5W50 full synthetic, and that VW and BMW were using Castrol synthetic as their OEM oil and recommending a 15,000 mile change interval, I switched to 5W50 Castrol and that's what I've been running in the old heaps. I use the same oil in the new Cherokee, but for that one I use the factory-recommended 5W30.

The aux tranny cooler came with the tow package or the off-road package. It was not standard, and I don't think it was offered as a stand-alone option. Maybe in some years as part of a heavy-duty cooling package? Or a fleet package (like for police departments, etc.)

Crutchfield sells (or used to sell) the correct speakers for that location, which are 4" round speakers on a 4" x 6" rectangular plate. I bought a set a couple or three years ago. Havn't looked recently to see if they still have them, but it's easy to make your own. In general, round speakers work and sound better than ovals (IMHO).

There is usually a tag on the front differential. There usually was NOT a tag on the rear differential. Everyone's idea of the "ideal" gear ratio is different. And a lot depends on how you plan to use the vehicle. If you plan on a lot of high-speed highway cruising, you might want a ratio that'll keep the RPMs down somewhat and yield (maybe) better gas mileage. If the truck is a weekend warrior and won't see a lot of highway use, more gear makes it more driveable at lower speeds. For comparison, based on 235/75R15 tires, here are the RPMs in 5th gear for 65 MPH with different gear ratios: 3.08 ==> 1724 3.54 ==> 1988 3.73 ==> 2095 4.10 ==> 2303 To put that in perspective, my 1966 Rambler American with a 3-speed manual tranny, 3.08 gears and small-ish tires ran 2500 RPM at 60 MPH, and 3000 RPM at 72 MPH. And it would cruise happily at 72 MPH all day. You can easily run 4.10s with the 235s and not be concerned that you're "burning up the engine."

Just to keep us all on the same page -- is this in regard to the 86 MJ listed in your signature? So it actually has a radiator cap and catch bottle, not the pressurized bottle found on the 87 - 90 4.0L models? 2.5L or 2.8L? How old is the radiator?

The reason modern automotive cooling systems have pressure caps is to raise the temperature at which the coolant boils. Leaving the cap off, or running a cap that doesn't provide a positive seal, is just about guaranteed to boil off the coolant.

Ah, so. Yeah, that should work.

You still haven't mentioned the width of your factory rims. For a 4-cyliner 4-speed, I expect you have the steel rims with 9 rectangular holes around the outer portion of the web. That rim is a 15x6. All other Jeep rims for the XJ and MJ were 15x7. You can run 31x10.50s on the factory 7" rimes, but they are too wide for the 6" rims. And you wouldn't want to run 31s with a 4-cylinder 4-speed anyway. Frankly, I think you are about as big as you would be happy with right where you are. Tires with a larger diameter would only reduce your final drive ratio still more, and the 4-cyl 4-speeds weren't rocket ships in stock trim. One option would be to look at 60-series tires. Keep your outside diameter but get a wider tire. Just be careful that the wider tire doesn't rub the inside of the rear wheel wells.