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Discussion Starter · #21 ·
after days of searching I have finally found my answers. I kept asking repeatedly for anyone to tell me what made the 2WD VS 4WD springs so different and nobody could answer that question, they just kept referencing a computer that told them they were different without an explanation of how. I wound up going to a ram dealership near me and headed to their parts counter and asked them to bring me a spring for each truck 2 and 4 WD, they're identical. the difference is not in the coil springs, its in the shock absorbers. 4WD trucks are generally a little bit heavier because they have to carry the extra weight of the transfer case, front drive axle and front drive shaft so the shocks on a 4WD are just a little bit stiffer than those of a 2WD. The shocks will still fit a 2WD though as they're also the same design and fitment.
 

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after days of searching I have finally found my answers. I kept asking repeatedly for anyone to tell me what made the 2WD VS 4WD springs so different and nobody could answer that question, they just kept referencing a computer that told them they were different without an explanation of how. I wound up going to a ram dealership near me and headed to their parts counter and asked them to bring me a spring for each truck 2 and 4 WD, they're identical. the difference is not in the coil springs, its in the shock absorbers. 4WD trucks are generally a little bit heavier because they have to carry the extra weight of the transfer case, front drive axle and front drive shaft so the shocks on a 4WD are just a little bit stiffer than those of a 2WD. The shocks will still fit a 2WD though as they're also the same design and fitment.
Word of caution, identical looking and identical are not necessarily the same thing.

Swappable, yes. Identical? Maybe not.
 

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Discussion Starter · #23 ·
Well after measuring both springs with a set of dial calipers I would have to say that they're identical.
 

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White Lightning
2018 RAM 4500 Cab & Chassis, 6.7L Cummins, AS69RC transmission, four wheel drive, 60” cab to axle.
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Well after measuring both springs with a set of dial calipers I would have to say that they're identical.
But......did BOTH springs have the SAME part number?
 

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I'm not exactly sure what you mean by increasing the rate. Cutting a coil off shouldn't have any detrimental effects of you cold cut it with a bandsaw, I could see using a torch harming the metals integrity but if it is cold cut then it will still be the same overall space between each coil the same metal thickness, same diameters, everything would be the same, just shorter.
Spring rate, is the rate of compression per inch, so cutting a coil off increases the rate because the spring is shortened, less spring to compress, thus the rate is increased.

I still say you should just call one of the lift kit companies and ask for a recommendation.
 

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Spring rate, is the rate of compression per inch, so cutting a coil off increases the rate because the spring is shortened, less spring to compress, thus the rate is increased.

I still say you should just call one of the lift kit companies and ask for a recommendation.
Cutting a coil does not increase spring rate. It lowers the overall height. Spring rate is the measure of how many lbs it takes to compress the spring a given amount. Usually measured in inches. The only time cutting may change the rate is on a progressive rate spring.
You are in my opinion correct when recommending an aftermarket manufacturer. They invest a lot of time and effort engineering other than stock components. They speak the language of modification fluently.
 

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Spring rate? I’ll agree. Distance traveled divided by load. Noticeably so? Have to cut more than one or two. Load rate? No. It’ll still coil bind at a given wt. it’ll just travel a shorter distance to get there.
 

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As an example the pictured 68172107AA spring can come on 13 - 18 2500/3500 2wd or 4wd. Same for the 68172108AA. The 68172099AB on your truck, Txtraveler, only show up on 3500 2wd or 4wd. This stuff is hard to sort out.

Check out wranglerforum to see the people there trying to adjust rake or lift their jeeps. They go through the same thing.

Seems pretty random at times with all the different springs out there but I am sure all the sagacious engineers and assembly line workers know exactly what they are doing. Maybe they decide what springs based on a lottery or their favorite number.
Is the case with the rear coil springs as well? I'm trying to do a reverse level on my 2500.
 
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