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blazerbrad · 05-21-2013, 10:21 AM

Big difference between doing fairly hard rock crawling like the H2 above and pulling a trailer down rutted roads. I have an '03 2500HD with 132k on it and my dad had an '02 2500HD with just under a 100k when he sold it. Mine has spent a decent amount of time in fields and minor off-road stuff including pulling trailers around in 4 low and has been stuck with the trailer several times also. Also beat on it quite a bit trying to get back up a dirt/grass path from down in a valley after a rain (multiple full throttle attempts, speedometer read 40 mph but truck was barely moving). Never have broke anything or even replaced any parts, but I am getting ready to go through the front end as routine maintenance. I also grew up in a farming community and worked construction and there were tons of IFS Chevy trucks running around that got used hard. My cousin, while he does a good job on maintenance and keeps stuff clean, is notorious for running the hell out of vehicles. His trucks spend almost every day in some sort of off-road condition and pull big goosenecks with construction equipment around during the week, and oftens spent the evenings and weekends working on the farm pulling wagons. He has never broken any IFS parts either.

Now I'm not saying these parts are bulletproof as if you put big tires, lockers, and try to run the Rubicon every weekend they will break. But for what these trucks are designed for (reasonable size tires, farming, construction, mild off-road) they work pretty good. In other words, for towing the off-road toy down unimproved roads and what I would expect for it to see off-roading (where a Sub can fit and not get torn up) I wouldn't worry too much.

For tire size we ran 285/75R16's (about 33x11) on the stock alloys on both the '02 and '03 with no torsion bar cranking but did require minor trimming in the front. This involved the plastic inner fenderliner and front valance. On my '03 I recently switched from the factory wheels to aftermarket 16x8's with the exact same size and brand of tires and started having rubbing issues. It's just on the plastic inner fenderliner and does no damage, but makes a lot of noise. So going from a 6.5" to 8" wide wheel with about the same backspacing made a substantial difference in how the tire fits when turning (arc is muc

Cranking the torsion bars in moderation is okay. The biggest thing that causes the horrible ride is when the bars are cranked enough the a-arms are resting on the droop stops, meaning when you hit a pothole the suspension can't drop down any. The higher the angle on the CV's the more wear and less total strength you have....biggest issue is the wear and especially wearing a hole in the boot as once the grease goes the joint will fail shortly afterwards. Tierods and balljoints are the same way as the more angle the more stress on them, plus add in the bigger tires that is generally associated with cranked bars.

Last year I picked up a set of 17" H2 wheels with 35x12.50's BFG tires and test fitted them on my '03. Personally I thought it was going to require too much work to make them fit (keep in mind I run 40" tires on only 4" of lift on my K5 Blazer so big tires/little lift and massive trimming is something I'm quite familiar with). Even by jacking up the frame and letting the front suspension droop to simulate cranking the torsion bars 2" the tire were not even close to being able to turn full lock in either direction without getting into hards parts (i.e. just not plastic stuff). I'm sure you can do it, and other people have, I just was not willing to bother with it. Part of the issue was I also did not want the power/gearing loss of the tires.

05-21-2013, 10:21 AM	#10
blazerbrad - CORE Member - Join Date: Feb 2007 Posts: 831	Big difference between doing fairly hard rock crawling like the H2 above and pulling a trailer down rutted roads. I have an '03 2500HD with 132k on it and my dad had an '02 2500HD with just under a 100k when he sold it. Mine has spent a decent amount of time in fields and minor off-road stuff including pulling trailers around in 4 low and has been stuck with the trailer several times also. Also beat on it quite a bit trying to get back up a dirt/grass path from down in a valley after a rain (multiple full throttle attempts, speedometer read 40 mph but truck was barely moving). Never have broke anything or even replaced any parts, but I am getting ready to go through the front end as routine maintenance. I also grew up in a farming community and worked construction and there were tons of IFS Chevy trucks running around that got used hard. My cousin, while he does a good job on maintenance and keeps stuff clean, is notorious for running the hell out of vehicles. His trucks spend almost every day in some sort of off-road condition and pull big goosenecks with construction equipment around during the week, and oftens spent the evenings and weekends working on the farm pulling wagons. He has never broken any IFS parts either. Now I'm not saying these parts are bulletproof as if you put big tires, lockers, and try to run the Rubicon every weekend they will break. But for what these trucks are designed for (reasonable size tires, farming, construction, mild off-road) they work pretty good. In other words, for towing the off-road toy down unimproved roads and what I would expect for it to see off-roading (where a Sub can fit and not get torn up) I wouldn't worry too much. For tire size we ran 285/75R16's (about 33x11) on the stock alloys on both the '02 and '03 with no torsion bar cranking but did require minor trimming in the front. This involved the plastic inner fenderliner and front valance. On my '03 I recently switched from the factory wheels to aftermarket 16x8's with the exact same size and brand of tires and started having rubbing issues. It's just on the plastic inner fenderliner and does no damage, but makes a lot of noise. So going from a 6.5" to 8" wide wheel with about the same backspacing made a substantial difference in how the tire fits when turning (arc is muc Cranking the torsion bars in moderation is okay. The biggest thing that causes the horrible ride is when the bars are cranked enough the a-arms are resting on the droop stops, meaning when you hit a pothole the suspension can't drop down any. The higher the angle on the CV's the more wear and less total strength you have....biggest issue is the wear and especially wearing a hole in the boot as once the grease goes the joint will fail shortly afterwards. Tierods and balljoints are the same way as the more angle the more stress on them, plus add in the bigger tires that is generally associated with cranked bars. Last year I picked up a set of 17" H2 wheels with 35x12.50's BFG tires and test fitted them on my '03. Personally I thought it was going to require too much work to make them fit (keep in mind I run 40" tires on only 4" of lift on my K5 Blazer so big tires/little lift and massive trimming is something I'm quite familiar with). Even by jacking up the frame and letting the front suspension droop to simulate cranking the torsion bars 2" the tire were not even close to being able to turn full lock in either direction without getting into hards parts (i.e. just not plastic stuff). I'm sure you can do it, and other people have, I just was not willing to bother with it. Part of the issue was I also did not want the power/gearing loss of the tires.