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February 2002 Techline

Posted in How To: Tech Qa on February 1, 2002
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What's That Noise?
QI own a 2001 Wrangler that I like to take camping, usually in the middle of nowhere, and usually during the summer. So I like to remove my Jeep's doors. The problem is that when I'm in the campsite I like to leave the keys in the ignition so I won't lose them. When I do that, there is that incessant beeping if the door is open. On my last truck, a 1996 Dodge Ram, it was very simple to remove the buzzer. I can't seem to find the Jeep's beeper. Can you help?Matthew D. FellowsLong Beach, California

A Dave Harriton at AEV (which builds stretched TJs,, 406/251-2100) tells me that what you're hearing is actually a tone generator that is integrated into the dash circuit. So it cannot be removed. Dave says that there are four switches that activate the unit: a driver's-door-jamb switch, a driver's seatbelt switch, a key-in-ignition switch, and the headlamp-on switch.

You might be able to accomplish your goal by eliminating or bypassing the door switch, but doing that could cause other issues. As far as we can tell, there are no simple ways to solve this problem.

The Fix Doesn't Fix It
Q I read with interest your answer to Jason Herrick's question regarding heating problems with his Bronco ("Par-Boiled Bronco," Oct. '01). My overheating problem is not with a Bronco, but with a Jeep Wagoneer. The things you said to try on Herrick's Bronco didn't seem to work on my Jeep, which still overheats. Any clues that will help me with my Wagoneer?Mike SmithLos Angeles, California

A I've heard from Jason since that letter, and my answer, appeared in Four Wheeler. He told me that his heating problem stemmed from a slight leak at the thermostat housing. This leak prevented any build-up of internal pressure. It should go without saying-but apparently it does not-that the entire cooling system must be completely sealed. It must exhibit no leakage whatsoever. This naturally includes the radiator cap. It must have a tight seal that holds pressure. Check the cap and the radiator's sealing lip for full contact, as the cap certainly is part of this equation.

Now, to your Wagoneer: I am not sure if it has an overflow catch tank. These overflow tanks do more than just catch the hot coolant. They also cycle the coolant as it heats and cools. That does two things-it keeps the radiator completely full of coolant, and it helps to eliminate any air bubbles in the system. Installation of a fan shroud, if yours is missing the stock item, would be a step in the right direction, but be sure that the shroud is big enough to pull air through the entire radiator, not just the radiator's centersection.

You might be tempted to turn to an electric fan, but I've got to tell you, I am not a real fan (pun, get it?) of electric fans, or flex fans either, for that matter. I believe that a fixed-pitch high-capacity fan that's driven by your engine's accessory drive belt is the best answer.

Now we come to something that is most likely the culprit. To get air to flow through the radiator into the engine compartment, air has also to get out of the engine compartment. Years ago I had a Wagoneer that had an overheating problem. I finally solved the problem by installing some hood vents and by cutting some two-inch holes in the inner fenderwells to allow air to escape. It made a world of difference.

Too Much Tire
Q I just bought a '91 Toyota 4x4 with a 22R-E four-cylinder and it can't turn the 32-11.50s on it. I've been wanting to run 38-inch Swampers but don't have the power, so I'm going to put a six cylinder in. What is your opinion of this, and do you have any suggestions that will help me get the 38s on the truck?Jon AnsleyElysian Fields, Texas

A Well I am sure that you can turn the 32s, just not very well in Fifth gear. Buick and Chevy V-6 engines are the most common engine swaps, but if you want to run the 38s, you have a lot of planning to do besides just an engine swap.

You need to look at all your options before jumping into this. First there is overall gearing. No matter what engine you go to, you have to keep the engine rpm in a range where the engine makes some power. This means lower gearing for both the axles and for the transfer case. Most people who run a tire that tall also run axle gears in the 4.86 range. There are some 5.38s and even some 5.71 gears available from Reider Racing (313/946-1330). However, with gearsets like this the pinion gear gets mighty small and thus becomes prone to breakage because of the leverage exerted on it by big tires.

I would suggest that the best way to go would be to install 4.86:1 gearing. Then, install either a 4:1 T-case reduction kit from Advance Adapters, a 4.7 Marlin Crawler (Marlin's Automotive, 209/252-7295) low-range kit, or one of the kits that allow the usage of two transfer cases in tandem. With the low gearing and the resulting torque multiplication, you then will run into other driveline problems such as broken frontends.

Now for the really bad news. There is no practical way to put 38s under your truck without going to a straight axle. Sure there are some specialty rigs out there-such as that owned by Top Truck Challenger Scott Ellinger-that run 36-inch tires with success, but the modifications read "expensive and extensive." I really suggest that you stick to a tire no taller than 35 inches. And if you want to eliminate breakage, 33s might be an even better choice. These are going to require a three-inch body lift as well as a three-inch suspension lift.

If you are going to swap to a solid axle, then Jon Bundrant at All Pro Off Road (909/658-7077) can help you out with the necessary conversion parts.

Both Advance Adapters and Downey Off Road (562/949-9494) have engine conversion kits to fit your needs. Do keep in mind the need to keep your vehicle emission-legal. Generally, that means that you must use an engine at least as new as that of the truck's, and all that engine's emission equipment must be transplanted into your truck and hooked up.

Building A Snow Plow
Q I am in the process of researching a truck for snow plowing. I don't have a favorite brand, but so far have looked at Ford, Chevy and Toyota. Heck, for the prices of the diesel option, I may end up purchasing a Hummer. The vehicle will also, of course, be used for four-wheeling the north woods of Michigan's Upper Peninsula.

None of the manufacturers whose trucks I've looked at offer a special transmission for plowing, and that concerns me. The OEM snowplow kits consist basically of suspension, alternator, and cooling packages.

Lastly, a limited-slip rearend seems unavailable with a diesel engine, as does any gear ratio lower than 3.73:1. All of this is important because I'm trying to decide on diesel versus gas and am wrestling with power and powertrain configurations as related to fuel economy. Do you have any suggestions?Jeff ParksVia the Internet

A Yes. My suggestion would be the Chevy Duramax diesel with the Allison automatic transmission. This transmission is very strong. Additionally, it has a very low First gear. That 3.73:1 axle ratio is perfect with this low First gear. This combination comes with a transmission cooler so overheating wouldn't be a problem. Chevrolet offers an optional limited slip, but I wouldn't expect great things from it.

Small-Block Swap
Q I plan to install a Chevy 350 into my Land Cruiser. I am trying to find information on the project. Have you done articles on the subject in previous issues?R. VieraVia the Internet

A We have done several such stories, but I think that your best bet would be to contact Advance Adapters (805/238-7000, and order up their "Toyota Land Cruiser Engine Conversion Kit" instruction manual. In it you will find just about every answer to any question you may have on installing the Chevy engine into your Toy.

There are quite a few shops that just deal in Toyota Land Cruisers. These include Downey Off Road Manufacturing (562/949-9494), Toyotas R Us (719/539-7733), and Land Cruisers Unlimited (208/687-2607). These shops perform conversions and sell conversion kits.

Keister Kicker
Q I just ordered an '02 Chevy 2500HD Crew Cab shortbed with the Duramax/Allison combo. Should be here end of August. It will be coming with 3.73 gears and 245/75R16 tires. I want to put on a 6-inch RCD lift with 35-inch tires. Will I need to regear, or will the Duramax be able to handle the taller tires? If not, what ratio would you guys recommend? Where would I get something like the Hypertech Programmer to recalibrate the speedometer and shift points? Also, does anybody make a power chip for this engine yet? My buddy put a power chip on his 2000 Dodge Cummins and it kicks butt. I am looking for the same type of gains. Any other performance modifications you could suggest I would appreciate.DaveChester, California

A Guess what, Dave, the new Duramax kicks butt without any modifications. I can say this because I bought one after participating in the initial pre-production comparison testing of the Chevy diesel versus the Ford and Dodge diesels. The Duramax is so new that the only thing that I know of in the form of modifications is a change in the exhaust system. It will most likely be a while before the aftermarket catches up with gears for this truck. So far, the only gear ratio available is the 3.73:1 from the factory. That's because this truck uses a different rear axle than the other GM HD trucks. They use the Corporate 14-bolt axle, which uses a 10.5-inch ring-gear. The 2500HD trucks powered by the Duramax 6.6L diesel use an axle built for GM by American Axle which uses a ring-gear that measures 11.5 inches in diameter.

As to the new engine and transmission combination being able to handle the 35-inch tire, that depends on what you plan to do with your truck. If you're going to haul 15,000 pounds behind it, then the answer would be no. If you're going to just four-wheel with it, and perhaps haul around a camper, then probably you won't have any problems at all.

A Grand Lift
Q In regards to your Jeep Grand Cherokee project ("Ain't It Grand," July 2000), I have a 1998 Jeep Grand Cherokee 5.9L Limited with the Quadra-Trac full-time transfer case. I need (want) to lift it. I called and asked one of Rubicon Express' phone reps about that company's 411/42-inch lift and was told that with the full-time transfer case, this much lift would tear up the front U-joints because of the resulting severe driveshaft angle.

How was your project Jeep affected after you lifted it? Please tell me that it really didn't affect the frontend too much. Would you recommend the 3-inch lift over the 411/42-inch lift?Judson MantheyCamp Lejeune, North Carolina

A Project "Ain't It Grand" used a 3-inch Terra Flex system just so driveshaft vibrations would not bother us. Yes, I do know of those using 4 inches of lift and more on Grand Cherokees, and yes, they do have driveshaft vibrations. The front shaft is quite expensive to replace but if you can live with the vibration and the price of a new front driveshaft every 30,000 miles or so, go for it.

Unfortunately, the vibration also affects the bearing on the pinion shaft and in the transfer case. How much damage it does is unknown. A solution would be to replace the original frontend with a high-pinion Dana axle to reduce the driveshaft angle.

Pick-A-Part Bronco
Q I recently bought a '75 Ford Bronco chassis. I want to convert it to disc brakes but don't want to buy an expensive kit. I have heard you can swap in parts from other trucks instead. First I heard that you could directly replace the old knuckles with those from a '78 Bronco with disc brakes. Second, I heard that you could use the knuckles from a '70s Blazer. I have been told that you use the Chevy knuckles and the Chevy calipers with the Ford rotors and spindles. Third, I have been told that you can use the knuckles and brake system off a newer truck, such as an '88 F-150. What can you tell me about this?Andrew BernardVia the Internet

A To get the straight scoop I went to Jim Cole, product manager and all around good guy, at James Duff Enterprises (360/683-2160, Jim works with customers every day on this stuff so he's pretty knowledgeable about it. Here's what he advises:

"You can use '96 and older fullsize F-150 and big Bronco knuckles, caliper brackets, spindles, and hubs, but you'll need custom steering linkage to work (i.e. cut and rethread the fullsize stuff to fit). The '78-'79s work best for this since they share the same pitman arm spline taper as the '67-'75 Broncos. Available from James Duff Enterprises are custom knuckles that use the steering arm configuration of the '75-and-older Bronco with the spindle-mounting pattern of the '75-'96 F-150 and Bronco. The knuckle is also beefed up with additional material in high-stress areas and uses stronger iron than a stock knuckle. The caliper bracket is designed just like the Ford item, with the same stronger iron used. Rotors, wheel hubs, and calipers are stock-type '76-'96 stuff. This setup means being able to keep all Ford items, and it uses off-the-shelf items (with the exception of the knuckle) for easy replacement down the road. The biggest benefit here is it's all in one kit, with no mismatched parts, so you know it works well. Also it is stronger than stock, uses stock steering components, and is basically how Ford did it. If replacement parts are needed, just hit the local auto parts store and collect the parts for a '76 Bronco."

Transmission Trauma I
Q I own a '97 Ford F-250 Crew Cab with a Power Stroke diesel, a five-speed tranny, and 4.10 gears. I bought the truck new and it was used as a work truck for three years. It has 137,000 miles on it. The problem is with the transmission. At 39,000 miles the synchronizers started going out. Now it's at the point where I need to fix it. My question is whether I should or not. I could put a six-speed manual tranny in it from a '99 or newer Ford F-250 or F-350. Will it bolt up directly or will it require a lot of modifications? An alternative that I would prefer is to convert it to an automatic. How much trouble would that be?Brent MurrayFrontenac, Kansas

A I consulted Ford truck guru Mike Kelly of Helena, Montana. He said that a six-speed will bolt right in. But to make this swap work, you will need a different flywheel and clutch, as the six-speed does not use a dual-mass flywheel like the five-speed does. Also, the output splines on the six-speed are much bigger than on the five-speed, so you will need the matching NV27 (manual shift) or NV273 (electronic shift) transfer case to complete the swap.

If you choose to go with the automatic, you will need some kind of a transmission-fluid cooler, a new steering column or a shifter, and most importantly, the correct engine-management computer and all the sensors and wiring.

Transmission Trauma II
Q My Ford F-150 has a four-speed automatic with Overdrive. Lately the trans is behaving strangely. Sometimes it shifts between First and Second or Third and Fourth gears really hard. Other times it seems to take a long time to make the shift. One repair shop tells me it's the computer while another tells me that the transmission needs to be rebuilt. Who's right? I hate to spend the money on rebuilding the trans only to find I need a new computer or vice versa. By the way, the truck has 95,000 miles on it.Jess WillisIndianapolis, Indiana

A Either shop could be right. A malfunction within the electronic control unit-the computer that oversees the functions of your truck's engine and transmission-could cause the erratic shifting. But my guess is that because of the mileage accumulated there is excessive wear of the line-pressure modulator sleeve, allowing oil to leak past this valve. If there is a lot of wear, the valve can stick, building up pressure until there is enough pressure to release it, thus causing a harsh shift. If this is indeed the trouble, you will in time reach a point where the trans may not even shift. I suspect it's time to rebuild that trans.

Bigger Gears, Or No?
Q I have a 2000 F-350 Super Duty with an 8.5-inch suspension lift and a 3-inch body lift on 42-inch Super Swampers. I have a stock Sterling 4.30 rearend. I will be towing a 21-foot boat that weighs 3,800 pounds. Will the existing rearend be all right, or should I change it?Mike KerberSimi Valley, California

A The rearend is plenty strong enough for the application, but the gearing isn't low enough for the application you mention. The 4.30:1 was the gear ratio that Ford figured it needed for a tire that was about 31 inches tall. With your 42-inch Swampers, your rolling radius has increased by about 5 inches. The practical effect is that your truck now has gears in the 3.30 range. If you think performance is lacking now, guess what it will be like with the boat in tow. To get back to factory equivalency the proper gear ratio to swap to would have to be in the 5.60:1 range. Unfortunately, the lowest ratio I could find for your Ford rearend was 4.56:1. So it all comes down to what you can live with or how much money you want to spend.

The way to lower gearing is to swap the axle out for a Dana 70 or a GM 14-bolt. To do this swap you're going to have to make some modifications to driveshaft lengths, spring pads, and brake hook-ups. Both the GM and Dana axles have 5.13 gears available. But that brings up another problem. Your frontend is a Dana 50, a hybrid that uses a special ring-gear that is about the same size of a Dana 44 but a lot heavier. According to our sources, the lowest gear ratio available for it at the present time is 4.56:1.

Willie's Workbench
Air Filter Maintenance
Every four-wheeler knows the importance of a clean engine air filter. But sometimes we don't maintain this important filter properly.

While factory-style pleated paper filters work just fine, some people feel that an aftermarket oiled gauze filter offers not only better air flow for improved performance, but better filtration and longer engine life. Whatever your filter element choice is, here are a few tips that will help prolong both filter and engine life with minimum effort and expense.

After a trip over a long, dusty trail, common practice is to take a paper element out of its holder and strike it against an object to dislodge as much dirt and crud as possible. That's fine, but don't do this with such force as to distort the filter's rubber sealing edge.

Some people like to use compressed air to blow their filters clear. This isn't a particularly good practice because excessive pressure can damage the filter's fibers. If you do choose to use compressed air, always blow from the inside of the filter toward the outside, and keep the air pressure fairly low.

You can let the oiled gauze filters get pretty dirty on the outside. In fact, up to a point, the dirtier they get the better, as the crud makes a barrier against fine dirt particles. How dirty is too dirty? That's a tough question, as even when the filter is so dirty you don't want to get near it, it's still flowing sufficient air. Cleaning time is a guesstimation.

No air filter element likes water. While the oiled gauze ones seem to tolerate and repel water better than paper ones, you should really find some other way to keep water away. This can be as simple as a nylon stocking over the opening or as complicated as a snorkel. For open-element air filters that sit directly on top of the carburetor or throttle body, there are special tight-weave nylon outer filters that help prevent water entry. It could be necessary to make some type of a shield around the front half of the filter to prevent entry from splashed water during a stream crossing. Attach the shield to the air cleaner's lid, or even to the hood itself. On my own Jeep the shield is fastened to a crossmember that goes across the engine from the shock towers.

A good air seal between the filter and its container and the carb/throttle body is important. I like to use a long-fiber grease on both the gasket and the filter's rubber seal from lid to base to ensure no dirty air can find its way into the engine.

Next time you're doing maintenance to your rig take a few minutes to look at the filter. Time spent on it is equal to money saved on engine repair.

Where To Write
Address your correspondence to: Techline, Four Wheeler, 6420 Wilshire Blvd., Los Angeles, CA 90048-5515. All letters 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 Due to the volume of mail, electronic or otherwise, we cannot respond to every reader, but we do read everything.

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