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.
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, www.advanceadapters.com) 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.