What's The Difference?
Dear Experts,
What's the difference between all-wheel drive and four-wheel drive? We're looking to buy an all-wheel-drive GMC Safari and want to be able to take it on sand. One person told me they're the same, except all-wheel drive is computer controlled, whereas four-wheel drive is manual. Someone else told me they're very different but couldn't explain. We haven't been able to get a straight answer from anyone.
Spelly Furello
via the Internet
The difference, in a word, is gearing. We define an all-wheel drive system as one that allows engine torque to be sent to both front and rear driveshafts, without the benefits of a dedicated low-range gear. Some all-wheel drive systems, under dry-weather conditions, are front-wheel-biased (e.g., the Honda CR-V, Toyota RAV4, Subaru Forester) while others are rear-wheel-biased (GMC Safari, 5.0-liter Ford Explorer, Olds Bravada). We think of these alternatives as the less rugged, "all-weather" choice.
We define a four-wheel drive system as those offering a low-range gear reduction (i.e., a transfer case), which offers improved performance in slow-speed outback conditions, not to mention providing a big assist for boat towers. Most four-wheel drive systems are "part-time'' setups; in normal circumstances, they can run in two-wheel drive.
A third category is necessary here. Full-time four-wheel drive takes the best of both worlds, running power to both axles when needed, with a dedicated low-range gear for heavy towing or steep hill climbing; some examples include the Toyota Land Cruiser, Range Rover, Fords Expedition, and Chevy Tahoes. Computers do most of the wheelspin/speed-sensing work. The advantage is increased all-weather readiness; one of the trade-offs is reduced fuel economy.
The GMC Safari you refer to uses a Borg-Warner transfer case with a computer to control a wet clutchpack to distribute power to the front driveshaft. We're told that as much as 35 to 40 percent of engine torque can be sent to the front wheels within milliseconds of detected rear wheelslip. We think you could drive it on sand, with skill and the proper tire pressures, fairly extensively-just keep an eye on the transmission temperature.
Engines In Half-Tons
Dear Four Wheeler,
I've heard the Big Three are doing something different with the 1/2-ton truck engines for 1999. Is Chevy bringing back the 327 and 383 strokers? Will Ford be supercharging? Will Dodge be bringing back the 429 Hemi? What have you heard about these engines? If this is so, will the engines be available for purchasing and swapping into older trucks?
John
via the Internet
Chevy is bringing out three new V-8 engines that are born from the new Corvette 350 motor: the Vortec 4800, Vortec 5300, and the Vortec 6000. The latter will only be offered in the 3/4-ton Chevy/GMC pickup.
We know that Ford is playing with a sport-truck-type 5.4-liter V-8; it's rumored to include a supercharger option, but we've heard nothing definite. We do know the next year's Lincoln Navigator, with the 5.4-liter Triton V-8 standard, will get a four-valve aluminum head and give the motor more than 300 horsepower. We assume it will eventually make its way into Expeditions and F-150s.
We've heard nothing about the 429 coming back to Dodge, and we'd be surprised to see it, considering Dodge's current powertrain lineup and especially with CAFE (Corporate Average Fuel Economy) numbers slated for revision.
Ram Tank Options
Dear Four Wheeler,
Do you know if there is a larger tank available for a '98 Dodge Ram 1500 Quad Cab shortbed? I thought the same configuration in the 3/4-ton allows for a 34-gallon tank, which leads me to believe it would fit underneath my 1/2-ton. Bottom line, I need more gas. Is there a tank I can swap in? Is it safe to add an auxiliary tank?
Jim Kay
via the Internet
According to our sources, the shortbed will only allow the 26-gallon tank, with the 34-gallon tank available in all other configurations. Space constraints due to the exhaust and transfer case make venting a larger tank difficult.
It's harder to get auxiliary fuel tanks these days, since the EPA and other government agencies have imposed extensive regulation in the name of safety and emissions law. Transfer Flow (Dept. FW, 1444 Fortress St., Chico, CA 95973, 800/442-0056) has several in-bed, replacement, and auxiliary tank options to choose from. All of their tanks are safety-rated.
Military Vehicle Phones
Greetings,
In the September '98 issue, there was an advertisement for Military Vehicles Magazine. Do you have the phone number? Are there any other M-37 sources you know about? Finally, can you give me a source for places to ride my ATV?
Michael Myers
Greensboro, NC
Military Vehicles Magazine has been a long-time advertiser in Four Wheeler and, from what Editor Dave Ahl tells us, it's growing from month to month. You can call him at 973/285-0716. As to where to ride in your area, you can contact the National Off-Highway Vehicle Conservation Council; they can give you information about where to ride. The Council's Website also has a Trail Info page that eventually will have state-by-state listings on OHV areas. Contact them at 800/348-6487 or find them on the Web at www.nohvcc.org.
Finding The Right Index
Dear Editor,
Was hoping to find an online list of available back issues. I own an '85 Bronco, and need info about lifts, frames, alignments, and all things Bronco. Is there any help available to locate specific back issues by subject? My wife says I need a hobby. This could be a good name for this old Bronco: "Hobby Horse."
Jack Page
via the Internet
We've made it a habit, the last several years, to include our Road Test Index in every March issue (see March '98 for the most recent); the Index lists nearly all of the road tests, comparos, and project vehicle stories that have appeared in the magazine over the past 36 years. We featured a Bronco suspension lift article in last month's issue, and another suspension kit is featured this month on page 96. We've also run steering, exhaust, and fuel tank swap stories (Feb., Oct., Dec. '94, respectively). We even have a listing of our most requested past articles.
A Special Thanks
Dear Editor,
I just finished reading "Backcountry Ballet" (Aug. '98) and would like to note that I actually broke my locker on top of Black Bear Pass, not before Ingram Falls. I would also like to thank Fred Perry (Clemson 4 Wheel Center of Clemson, South Carolina) and his brother Steve for helping me check out the damaged rear locker, then leading us down the mountain to Ouray. In case you were wondering, simply hoping the locker would work didn't seem to help, so we dropped the rear driveshaft and drove it back to Telluride. I'd also like to thank the group of Hummers that followed me back to Telluride.
Dewayne Catchings
via the Internet