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4x Forum Editorial

Posted in Features on November 1, 2007
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Send questions, comments, and suggestions to: 4 Wheel Drive & Sport Utility MAGAZINE, Attn: Christian Lee, 2400 E. Katella Ave., Ste. 700, Anaheim, CA 92806, or

Good and Bad of Propane
Comment: I have used propane for close to 20 years on everything from Ford 4x4s to Chevy Suburbans. It has always proven to be a good, clean-burning, reliable fuel. In Canada, the government used to have a program to subsidize the conversion, which it unfortunately discontinued. In some parts of northern North America, such as where I live, propane has one distinct disadvantage: It is always a very cold liquid under pressure which, when released from the bottle, changes into a gas. As long as the outside air temperature is above -42 degrees C (-40 degrees F and -40 degrees C are the same), this change of state can happen. If it gets colder than that, the propane stays a liquid and will always flood the engine. Believe it or not, I have held a Styrofoam cup under the vapor hose and filled it full of liquid propane

The physics works the other way in hotter climates as well. If you run out of coolant in your radiator, the vaporizer will not warm the liquid enough to vaporize it and you'll get a giant ice ball under your hood even at 100 degrees F. You won't turn a wheel - it's just like running out of fuel.Deryle PennerGrande Prairie, Alberta, Canada

A: Deryle, thanks for your response to the propane conversion article ("Samurai Propane Coversion," Aug. '07). You bring up some good points, and our physics lessons from long ago aren't fresh enough to dispute any of them. However, we did speak with Cary Gleason of in Phoenix who reports absolutely no hot-climate issues using the company's systems, provided the engine is well-maintained and in proper running condition (a loss of coolant in the radiator will have adverse effects on gasoline-powered engines as well).

In hotter climes, such as Arizona, Cary suggests filling tanks to 80 percent to allow for heat expansion, and also to have a relief valve rated at at least 170 psi in place so the tank won't become overpressurized. As for colder climes, such as in the Great White North, Cary recommends use of a bottle blanket to heat the propane bottle so that it will build the necessary pressure to convert the liquid propane to gas and power the system. Provided the propane bottle is warm enough to build ample pressure within the system, a propane conversion could feasibly operate in temperatures exceeding -100 degrees F. For more information about propane conversion systems, contact at (480) 430-8033 or

Cooling Questions
Q: Great article on upgrading the cooling system on the 4.0L XJ ("Keep Your Cool," Aug. '07). I'm in the process of flushing my cooling system and have purchased the FlowKooler water pump (I already have one on my CJ) to replace the leaking stock unit. I will also be purchasing the high-flow parts from Turbo City just as you did. I have a couple of questions though.

It says that you had a 180-degree-F thermostat installed, which will give you better gas mileage. I didn't understand this. I thought this would cause the vehicle to run cooler than it was designed to, which in turn would use more fuel as the computer would think that the engine was not fully up to operating temperature.

Also, did the lower radiator hose contain a spring? This is recommended by FlowKooler, and I am having trouble finding this part. If you didn't have a spring installed, have you had any problems with the hose collapsing?

Thank you for your time and keep up the great work on your magazine!William Bakervia e-mail

A: William, I'm glad you liked the cooling system article. My Cherokee really came back to life with a properly functioning cooling system in place, and everything seems to be running smoothly. You are correct that the 180-degree-F thermostat will use a bit more fuel than the stock thermostat. The article should have stated that the 180 would offer better fuel economy than the 160-degree-F thermostat, which is also offered by Turbo City. That is where I was drawing the comparison. Sorry for any confusion.

As for the lower hose, I used a Goodyear hose from Summit racing and haven't had any collapse issues. According to FlowKooler, most modern high-pressure radiator hoses use an internal coil and are sufficient for use when installing one of its high-flow water pumps. The company also manufacturers a variety of high-flow water pumps for street-rod vehicles that may use older-style or custom hoses that may not withstand the higher flow, and this is why FlowKooler recommends use of high-pressure hoses with internal coils. If you're having trouble finding the appropriate radiator hose, you may have to buy a universal-style hose and modify it to fit, or maybe bring the old hose with you to the parts store and find one that matches the closest. Thanks for reading.

We Have Attitude
Comment: I enjoyed the pictures in the Moab Easter Jeep Safari article (Aug. '07), but then I read the article and found an enormous display of attitude. Let's see... official run is paying, nonofficial is nonpaying - either way you get the ATTITUDE. The last time I looked, anyone can four-wheel on public land and not pay some 4WD organization. I used to belong to a large club (Ocala Jeep Club) and found some of the most unfriendly people I've ever met. Based on the article, if I had an inclination to join a club I would not join. I guess the faster you go on the trail, the more money you will make by selling trinkets from your organization.

I have been on Jeep Jamborees and had a lot of fun even though we met people (nonofficial/nonpaying) on the trails. I also have been all over Upper Tellico with friends and had even more fun. Sure, things can sometimes get bottled up, but I tend to simply enjoy the time on the trails and chat with the people I meet - and they don't have to pay for the privilege.

It doesn't matter where you go or what you do, there will always be some inconsiderate boob not using common sense. I will continue to ride trails without the benefit of some half-baked organization. I will do this when and where I choose, as I have earned that right unlike most peopleTom Mintz, USMC Retiredvia e-mail

A: Tom, while I can appreciate your desire to go wheeling on your own or with pals rather than joining a club, I think you've taken amiss the purpose of 4WD clubs as a whole as well as the message that I was attempting to convey in the article. You certainly do not have to pay to go wheeling if you choose not to, but remember that the Moab Easter Jeep Safari event is hosted by the Red Rock 4-Wheelers 4WD club and has been scheduled for the same time each year since its inception. If you do not want to be part of this official event, simply visit Moab at a different time of year when the event is not taking place. That way, everyone will benefit: The paying participants will get to enjoy a guided trail ride hosted by the Red Rock 4-Wheelers during the event, and you're free to explore whatever trails you desire (without running into any of the many guided trail rides) the other 350 or so days of the year.

Concerning your assertions about 4WD clubs (particularly that of the Ocala Jeep Club), I must say that you are way, way off base. The purpose of most 4WD clubs is more than just banding together as a group of friends, it's a banding together of our coculture as a whole. Ever heard the phrase Strength in numbers? That's what's effected when we join clubs. Most clubs give back to the trails and land they use by establishing volunteer work days and completing trail repairs so everyone (not just their club) can continue wheeling that particular area. Many not-for-profit clubs also hold events to raise money for land-use rights and defense against unfair land closures. The hosting not-for-profit club usually barely covers its costs at these events.

A number of 4WD clubs also volunteer their vehicles and time to local search-and-rescue operations, greatly aiding local law enforcement and fire personnel. Also, just so you know who IS paying for the privilege to wheel areas such as Upper Tellico, where you and your friends have had fun without having to pay, members of the Southern 4WD Association performed extensive trail maintenance in that area in 2006, providing in excess of $45,000 worth of volunteer labor, equipment, and materials. Even more volunteer trail work has been underway throughout 2007.

You may have earned the right to do what you want, Tom, and I thank you for your service to our country, but hopefully you'll also continue to do your part as a 4WD enthusiast to help ensure that future generations have the same opportunities and access to the great outdoors that we enjoy today. That's what most 4WD clubs I know of are attempting to do - even when they're trying to sell you trinkets from their organizations. Thanks for writing.

Note to readers
In the article titled "Grande Axle Upgrades" on page 54 of the July '07 issue of 4WD&SU, we detailed the installation of an ARB Air Locker and 4.56-ratio ring-and-pinion gears in a Chrysler 8.25 rear axle. It was stated in the article that we modified the ARB cross-shaft and ring-gear teeth so that the cross-shaft would clear the thicker aftermarket ring gear and allow the axle C-clips to be installed. Upon further research and in speaking with ARB representatives, we have discovered that this is not an ARB-authorized modification and should never be completed. Modifications to the cross-shaft or any other parts of the Air Locker may result in failure and will void the warranty.

The proper solution is to grind a small relief section from the ring-gear teeth so that the cross-shaft may be installed/removed without obstruction. More information on this procedure can be found in section 5.6 of the ARB Service Manual and is also available on ARB's website at

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