Episode 39

October 15th, 2009

Fabrication is the cornerstone of the custom truck world. “Fabricate This” brings the minds of fabricators onto the pages of your favorite magazine. Read along and try to keep up.

We are looking for fabricators from various shops to answer your tough customizing questions. Some of these fabricators are well known for their work over the years, while others may be from new shops that have yet to crash the scene. We encourage all fabricators to submit answers, but we have limited space, time, and resources to fit every submission. Our goal is to publish as many pertinent questions and answers as possible. If you have a question that you are interested in having answered, send it in and we will do our best to have it answered. The staff at StreetTrucks, Bob Grant and Cary Iaccino will do the best we can to police the answers for accuracy. Keep in mind that many fabricators disagree on what is the correct way to perform certain customizations. Therefore, “Fabricate This” is not responsible for the information given, or how it is implemented. And just because you see a shop or a fabricator in this column, do not overestimate their abilities. They may be perfectly able to render a truck useless with a few porous welds. Good luck, see you next month.

0607_st_truck_fabricators_column_01_sWe’ll start off this month’s column with some advice about checking out your ride before you hit the road on a long trek to your favorite shows. A few of you have e-mailed us about checking airbags, airlines, etc., in preparing for a trip that will take anywhere from a couple of hours to a couple of days to complete. We can answer this one from experience since rolling to shows in other states is a common occurrence for us.

Most of the components that need to be checked are underneath your truck, so jacking up and supporting your ride is the first priority. There are a couple of important things to do when jacking or lifting a truck with ‘bags. Air the truck up as high as possible, block the tires with wood or blocks, set your jack underneath, and begin lifting. Once it looks like your jack is lifting in the correct position, let the air out of the ‘bags where you have the jack. For example, if you are lifting the front, let the front air out of the ‘bags. Finish jacking the vehicle up to a height that will allow you to comfortably fit underneath, set up jack stands and carefully let the vehicle weight onto the stands. Repeat this for the rear of the truck. The reason for letting air out of the airbags when lifting your truck is to help eliminate the possibility of damaging your shocks, suspensions or airbags when there is no vehicle weight to keep them compressed.

Supporting the vehicle well cannot be stressed enough. A friend of ours was crushed beneath his truck when the air system gave out while he was working on it. It smashed his chest, ribcage and did significant internal damage. He said he could hear his pants and shoes rip as the blood was forced from his upper body down towards his feet. He sustained permanent damage and is fortunate to be alive.

Once you have safely set up your truck, grab a light or flashlight and crawl underneath. We usually will start with the airbags. It is very easy to find wear-marks or cracks in airbags. Typically, airbags rubbing on metal will cause abrasion marks. These types of marks will signify the future failure of airbags. If you see nylon strands, replace the airbags and fix the problem by adding clearance or resetting the ‘bags.

After inspecting the airbags, check the air lines next. There are various types of lines used, from copper to nylon to stainless hard-line to steel braided. The most common is the nylon DOT air line. This line is the most prone to failure. Most shops and enthusiasts use this line because it is the most cost-effective way to go. It is very reliable if installed correctly. Air line run near heat sources is the most common problem we have seen. Keep all the lines away from exhaust pipes, manifolds or headers. You should also check to make sure there are no lines that are rubbing or chafing on sharp objects.

Most road going failures will be related to airbags or air lines, but you can check a few more things before you start that 400-mile cruise. Check out the various suspension components and fasteners. Loose bolts/nuts, worn out bushings, damaged ball joints or tie rod ends can all be problems. Make sure your valves, compressors and air tanks are securely fastened. It sucks to roll down the road and the only dragging you’re doing is pulling your compressor behind you. Look for loose or damaged wires and check your air system’s fuses. Grab a squirt bottle with some soapy water and wet down all the air fittings, tanks, compressors, and valves to check for leaks. Kick the tires while you are at it, make sure you have all your lug nuts installed and correctly tightened. Don’t forget to check your tire pressure and tread wear before heading out.

If you’ve gotten successfully through all of that, you should be ready to roll. Jack your truck off the stands, pull them, let the truck down onto the tires, and stop. Put air back into the ‘bags for the tires that are on the ground. Then let the jack all the way down and the weight back onto the tires/suspension/airbags. Repeat for the other side of the truck and stop by the gas station for 3-dollar a gallon gas and check your fluids. Finish off your favorite energy drink and tread some pavement. And while we are talking about road tripping, we found a question that just might relate to your tow vehicle:

Low & Tow
0607_st_truck_fabricators_column_02_sHow do I bag a truck to be able to tow? I want the truck to be as low as possible. The truck is a dually, and I should have the bread to ‘bag it in the next couple of months.
Chris Marton

It’s amazing how many crew cab duallys are rolling out there, on airbags, towing show vehicles. You didn’t mention what type of truck you have: Dodge, Chevy or Ford. The rules for each of them are basically the same. Suspension and frame strength is one important aspect of design that cannot be overlooked. Using strong, thick steel plates and tubing is important. Stick to 1/4-inch wall or plate on just about everything. Don’t even think about saving weight, strength is more important. Be sure to use airbags that are rated at the correct weight for your vehicle and all it may be loaded with. You should be able to set up your truck to lay out, frame or body, and still have no trouble towing whatever you need down the road.

We like to use the cantilever suspension on the rear of most trucks for the increase in ride quality that it offers. But, when setting up a dually to tow a fifth wheel, we may add another ‘bag set over the axle or behind the axle to help with the weight the truck may see. Another option is to use the very large semi-type ‘bags on the axle to give you massive weight carrying capacity. If you have never airbagged anything before, stop by a reputable shop to find out what they recommend for your ride. There are probably two or three ways you can ‘bag the rear of your truck that should work out well if done correctly. But experience is important in getting it right, and you shouldn’t use your tow vehicle as your guinea pig.

Good luck.

Once again show season is upon us. We hope that all of you have had the opportunity to complete all the changes to your rides that you wanted to make before summer. Many people plan their vehicle construction around the show season and we are no different. We look forward to seeing all the new vehicles at various events this year, and only regret that we cannot attend all of them. 2006 should bring out a bunch of high quality, radical trucks. If you see something new, and want to know what it is or how it was done, please let us know. If we can help you out, the answers will be here.

Thanks for reading, see you next month.

If you would like to contribute to the “Fabricate This” tech question and answer column, we have made it as easy as possible for you. Unless you live detached from society, you can e-mail, snail mail or electronically post your questions. Visit our posting page on the IF Custom Web site. Simply go to www.ifcustom.com, click the link at the bottom of the page, then follow the instructions and post your question. Or send your question to:

Fabricate This
12423 Gladstone Ave. #27
Sylmar, CA 91342


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