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February 2011 Techline

Posted in How To: Tech Qa on February 1, 2011 Comment (0)
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Sometimes, readers are nice enough to share some information with me about certain topics.

Dan Lasich just sent me a link to a website, www.booksforcars.com, that really does have books for cars. In fact, they have just about anything you like when it comes to manuals-such as factory service manuals, owner's manuals, sales brochures, parts interchange manuals, and a host of others. It's well worth checking out. -Willie Worthy

Mystery CJ Clutch Chatter
Q I have an '85 Jeep CJ-7 with the 258ci six-cylinder engine and Borg-Warner T-5 manual transmission. There is a loud chatter noise coming from the clutch at speeds over 55 mph (tach reading around 2000 rpm), but only when gas is applied. It quiets and goes away when you let off the gas. I have a Centerforce Stage 2 clutch that I installed 1,000 miles ago, replacing the throw-out bearing but not the pilot bearing. What would cause this noise?
Matthew Krzeniak
Chicago, IL

A I am really not sure why the clutch should be making noise at highway speed and is (if I understand what you're saying) not making the noise at the same rpm and lower vehicle speed. Are you sure it's coming from the clutch and not the transmission? The T-5 is noted for having some bearing problems that will cause noise when in Fourth or Fifth gear, but usually the noise is foreshadowed by difficult shifting. Perhaps you can give me a few more clues?

Weird Dakota Four-Cylinder Exhaust Noise
Q I have a '97 Dakota with the four-cylinder engine. Yes, it is underpowered but I like the truck, so I just live with it. The problem I am having is an exhaust "puffing" sound. I think that it is coming from the exhaust manifold, but I'm not sure. Do you have any idea what this noise is and how can I fix it?
John Denver
Flagstaff, AZ

A This is a pretty common problem with the 2.5L engine that was used in both the 1996-99 Dakotas and various models of Jeeps from 1991 to 1999. It seems that the outer two studs on the exhaust manifold have a bad habit of shearing off. The bad news is that it's a lot of work to fix.

You have to remove both the intake and exhaust manifolds to have enough room to remove the broken studs. One trick is to weld a nut onto the broken stud, and while it's still hot, squirt the stud with a penetrating oil. The thermal shock of heating, when welding and cooling with the penetrating oil, really helps to loosen the bond of rust that is usually present. There are special stud-removal tools available-even Sears sells one. None of them are fun to use. The problem with welding the nut onto the stud is that you usually only get one chance, so the weld better be good. Otherwise, the stud usually becomes too hard to drill out.

Once the old studs are out and you're ready to install new ones, get the right ones from either your Jeep or Dodge dealer. I believe that they both use the same part number (p/n 06036193AA). Torque the new studs to 126 in/lb. An easy way to do that is by locking two nuts together on the studs' outer threads. Before you put it all together, you might want to consider elongating the outer holes on the intake manifold so that it can expand and contract without putting pressure on the studs. Torque all the bolts, starting with the center bolts and working outward.

Dana 44: Enough Axle for Ford With 40s?
Q I have a '91 Chevy shortbed single-cab with IFS. I've also got a high-pinion Dana 44 frontend out of another Ford, which I plan to swap into my truck. Now I want my truck to flex great with leaf springs. Any ideas on leaf springs?

Can I put a Ford NP205 transfer case behind my stock five-speed transmission? If so, what year of Ford should I look for?

I plan on using a kit from Sky-manufacturing.com to install the solid Dana 44 under my truck, and also plan on putting 38- to 40-inch tires under my rig. What size lift would I need to fit 40-inchers-plus with a good flexy suspension? Sky-manufacturing says with their kit it will give you six inches of lift over stock.
Ruben Ortega
Via fourwheeler.com

A First, you need to rethink your plans, especially if you really want to go to 40 inch tires. That Dana 44 is not going to live very long with 40s. In fact, it probably will not like anything larger than, say, a 37-inch tire, even with some quality aftermarket axleshafts. Yes, there are Jeeps running around with a 44 up front and big tires, but they also have a major weight advantage.

Okay, let's say you really have your heart set on some of those 38- to 40-inchers. To fit them, you're going to have to trim the fenders, move the axle slightly forward, and raise the truck at least four inches higher than the conversion kit will gain you. Even then, I suppose you will have to somewhat limit compression travel. The front-end lift is not a problem-you just order some 4-inch-lift springs of the proper length for their kit and capacity. However, to get the necessary lift out of the rear, you have to either use some tall lift blocks, some quite stout springs with lots of arch, a rear shackle flip, or a combination of all three.

Then true trail capability start to fail. The truck now sits very high, which translates to "tippy" on side hills, with overall lack of stability. You will have to figure out some way to control rear axle hop, and those so-called "traction bars" generally will limit suspension articulation. A lot of axle life depends on just how hard you plan to use the truck. If you're a "spare no prisoners, pedal to the metal" type of guy, then sell the 44 and start saving for the Dana 60 that you really need. If your driving style is a bit more even-tempered, then most likely a set of 35s or so may just be the right combination. Okay, I know lots of people reading this are going to say something like: "Oh, I run 40s and don't have a problem." Well, all I can say is, that's great, but either you're really nice to your truck, or you're lucky for now and that your axleshafts are going to eventually break when you're in a really nasty spot.

Now as to the transmission and transfer case: you didn't say which transmission you had. If it is the NVG3500, or the Muncie 5LM60, which was used in 1/2-ton pickups, don't even consider using it. If you have the NVG4500 five-speed, then you're good to go. As to what adapter you're going to need, as well as which transfer case, I suggest you contact Off-Road Design (970-945-7777, www.offroadesign.com). They are really nice guys, and I'm sure they can help you out.

Crossover Steering for Lifted Chevys
Q I am 15 years old and I have bought my first truck, a '79 Chevy 3/4-ton 4x4. I have a 400ci small block and a balanced flywheel for the four speed tranny. It has the NP205 transfer case, Dana 44 with lockouts, a limited-slip, and in the back has the full floating 14-bolt with a Detroit.

Did I make a good choice in buying this truck? I plan on putting a couple more thousand into it with a 6-inch lift and 36- to 38-inch tires. As of right now, it is in the shop getting long tubes and true duals installed. The reason why I ask is because I have been reading your magazine since I was 8 and trust the info you put in the pages of your magazine.
Mike Schrand
Via fourwheeler.com

A If you like the truck, the way it rides, handles, performs, if it fits the trails that you plan on running, and it is in good mechanical condition, then you made a good choice.

While your truck has "3/4-ton" running gear under it-and the 14-bolt is a great axle-the weak link is the front Dana 44 axle. This is the same axle housing that is under the "1/2-ton" trucks and has the same axleshaft size. The only differences are the bigger brakes, larger hub/spindle combination, and naturally, an eight-bolt wheel pattern. The bigger hub and spindle give it a higher load rating. In other words, it is designed to hold more weight.

If you really have plans to use that large of a tire, I suggest that you also invest in a set of aftermarket performance axleshafts. In my opinion, the axleshafts are going to be the weak link. Yes, there are a lot of Jeeps running around running 44 fronts with that tire size, but they also weigh at a lot less and don't put nearly as much load on the axleshafts. Your other choice-and probably a better one-is to keep your eye open for a single-rear-wheel 1-ton frontend, which will be a Dana 60. It will be a direct bolt in swap and offers a lot more overall strength.

Let's talk about the lift a bit. First, I suggest you get on the Internet and look at the various lift kits available. When comparing prices, make sure each kit has the same parts, such as quality shocks, longer brake lines, steering correction parts and so forth. Then read their installation instructions, which generally are also available online, so that you understand just what tools and other equipment are necessary. When going to that much lift, I really suggest that you also go to what's referred to as "crossover" steering. If you're not sure exactly what that is, take a look under any 1972-or-later Jeep to see how it works. Yes, you can also Google it, but to save you some trouble, take a look at what Off Road Design has to offer (www.offroaddesign.com).

Larger tires and that much lift will put more load on steering components, so make sure that tie-rod ends are in like new condition, the wheel bearings are adjusted properly, and-most important of all-that the frame where the steering box mounts is not cracked. Having the frame crack in this location is quite common, even on a stock truck, and most likely will happen when the truck is lifted and sees serious trail use. Several companies (including ORD) sell a really neat brace to support frames that are not already cracked, or a repair plate for those that are. You might also look at their rear-spring shackle flip kit as a replacement for new rear springs or lift blocks. It's a much better way to go. In fact, they sell a complete 3-inch lift that will fit 33s-and, with a 1-inch body lift and a bit of fender trimming, fit 35s. A lift of this height may be better for you, considering what I am sure is a limited budget. This way, you don't have to go with new rear springs, crossover steering, new driveshafts, and very expensive tires. Going to 33s or 35s by now are starting to look a lot better financially.

Tire choices are abundant and overwhelming, as there are so many to choose from. My guess is that your truck is going to be a daily driver, so pick a tire that will work great on the street and good on the trail. Stay away from nasty gnarly tread designs, as it's better to compromise in your choice for better highway handling and wear.

My final piece of advice is to take your time, research as much as possible every change you intend to make, and don't depend on information off the various forums to make your final decision. While there is some good information to be found on these, not all of it is correct. Oh, and finally, if you can find a 4x4 club in your area, become involved in it.

Where To Write
Address all correspondence to: Techline Four Wheeler, 831 S. Douglas St., El Segundo, CA 90245. You can also reach us by e-mail at fourwheelereditor@sorc.com; be sure to type the words "Tech Line" in the subject line. All submissions become the property of Four Wheeler, and we reserve the right to edit them for length, accuracy, and clarity. The editorial department also can be reached through the Web site at www.fourwheeler.com. Due to the volume of mail, electronic and otherwise, we cannot respond to every reader, but we do read everything.

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