Wheelhop Rx: D.I.Y. Traction Bars?
Q. You had a letter in the Dec. '09 "Techline" dealing with wheelhop, or some variation of it. Wheelhop has killed many trannys, U-joints, spiders, and ring gears. To cure that, you need what old-time drag racers called traction bars.
To replace the housing is going to incur considerable time and expense. So don't replace the housing, straighten it. How? There's an old-time roundy-round trick for this as a lot of roundy-round cars banged tires (rear) and bent the housings. Use a straight edge to determine where it is bent, then cut the housing on the opposite side and bend it straight-use a straight edge or dial indicator or whatever. I actually made a jig out of a piece of 5-inch channel and used some large C-clamps to pull the housing straight. I had some bent so badly that over a half inch of material had to be removed to get the housing straight. When it's straight, weld it up. I finally got smart (a little, not much), and welded a 5-inch piece of 1/4-inch flat stock on edge from one backing plate to the other.
A. Thanks for your input. I always like to hear different solutions to problems. However, conventional "traction bars" may work just fine for a car that only turns to the left, or for a drag race car with limited suspension travel, but on an off-road vehicle they are a "no-no." Why? Because they really limit suspension travel, and when articulation exceeds the movement of the traction bar, something has to break or bend, which it quite often does. Yes, there are some specially designed ones that work off of a unique shackle design, but one is better off designing the suspension system correctly in the first place to prevent axle hop from happening.
As to straightening an axlehousing using the method you describe, well, it may work, but it's not something that I would recommend. Generally speaking, the axletube of a vehicle used off-road usually bends right at the location where it enters the housing, or right at the spring mounts. Both of these locations would be difficult to locate and/or straighten with just a straight edge. Cutting the opposite side would allow you to more easily move the axle tube, but I just can't see that one could do it without some kind of giant C-clamp and lots of brute force. Then you have the problem of controlling the bend in the opposite direction from the heat of welding when you weld the cut back up.
I have scratch-built many axlehousings over the years and found it is quite difficult to keep them perfectly straight when the final welding is done. The only way that I've been successful in keeping them true is by using an "alignment bar," which mounts on bushings, that center it on the outer ends of the axle tubes as well as the carrier bearing location within the housing. I have used various methods to straighten bent housings over the years, ranging from applying heat and quenching, to a come-a-long and some special fixtures, to a very large 100-ton press and special fixtures. Any way you do it, it's a lot of work, and in reality has to be done with an alignment bar to ensure that the axletube is straight when you're finished.
Horsepower Tips For 5.9L Dodge
Q. I have a 2001 Dodge 3/4-ton extended-cab pickup with a 5.9L V-8. It's a nice truck, but it's a little short on power. It has stock exhaust and a K&N air filter system. I also have a JET performance chip installed that has helped somewhat, but this system is still underpowered when I haul and tow things. Do you have any ideas as to what would help me out here? As with most people during this recession, I have fairly limited funds. I'm pretty much figuring that my gas mileage will not get much better if at all, around 11 to 12 mpg, so if I could get some more horsepower out of this engine, I would settle for that. It's a very nice truck with several new items installed including a new automatic transmission, so I'm hesitant to get rid of a paid-off rig right now.
A. I used to own a '97 Dodge with the five-speed and 5.9L motor, so I am well aware of the overall lack of power and the poor fuel mileage. I went with some short-tube headers from a major manufacturer, a new low-restriction muffler and an aftermarket air cleaner. There was some gain from the air filter, but not a bit of gain in either performance or fuel mileage from the headers. I kind of expected that because of past experiences with short-tube headers, but had to give it a try and at the time they were the only ones available. Perhaps if you could find some long-tube headers you could gain a bit, but the payback will be a long time with only a mile or two increase in fuel mileage.
On a good day of interstate driving, I would see a high of 14 mpg if I was careful and kept the speed low. With a camper in the bed and pulling a trailer to, say, Moab, and fighting a headwind, sometimes I got as low as 5 mpg. The reason I am telling you all this is that there is not a lot to be gained with modifications. You have to live with your truck and accept the fact that it is paid for, and it just might be cheaper to pay for gas up front and not have truck payments. Oh, and I don't care what the TV ads say: In the real world, the new 3/4-ton 4x4 trucks do not get 20 mpg, but a lot closer to what you're presently getting.