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Discussion Starter #1
Alright my truck has a Pro Comp lift sitting on 37x12.5R20's. Torsion bars are cranked quite a bit as far as I can tell. (All the same as it came from the guy I bought it from).

Anyways its got dual Pro Comp EXP 3906 shocks in the front and single Pro Comp EXP 4009's in the rear. Out of all 6 of my shocks at least 4 are blown. Meaning they have lost ALL or at least most of their oil. My truck rides like a cement truck and driving over some rough freeway parts my truck bounces like crazy. Its horrible and prob close to being very unsafe at some locations and speeds, so I know its time to upgrade.

I know which shocks I want, but what I need help with is length and valving.
Eventually once these tires are dead (prob a year of tread left on these) I will be going to a 35" tire, backing my torsion bar bolts out as far as possible, replacing the 4" block with prob a 3" in the back and just lowering it as low as I can with the 35's.

With that being said can I buy a shock now that will still be a correct length when its lowered a couple of inches and put on 35's?

Im looking at the Bilstein 5160's and 5165's. I think I will have to go with the 5165's to match closest to my current shock lengths. But heres my other question. Did my current shocks blow because they suck or are they the wrong length? Ive heard this particular shock was made by Edelbrock, and I honestly dont have a clue if they are the correct length or not.

So should I just match my new shock as close as possible to my current ones or do I need to check if I need a new length? And again will this new shock work when I lower it a bit?

As far as valving I think I want it soft ecspecially with the duals up front soft should be fine. In the rear Im unsure. I always have my loaded toolbox and spare tire back there so prob what 250-300 pounds all the time. I dont tow very much maybe a few thousand pound trailers only a couple times a year. Plus Ive got airbags to help out when I do tow. So will soft work back there too? Or should I put a stiffer valved shock in the back?

Here are the current shock specs
Front Pro Comp EXP 3906 soft valving Extended: 22.225" Collaped: 14.19"
Rear Pro Comp EXP 4009 N/A valving Extened: 29.53" Collapsed: 17.49"

Sorry for the long post but whats your guys' thougts on my future shocks. Thanks in advance
 

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Discussion Starter #2
Bump...no one has any knowledge with this subject?
 

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Discussion Starter #3
So I guess Im just going to get a shock close to the same length as now and hope it works out fine now and with my future plans
 

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I'm not 100% sure, but I would try to call Norcal Nick tomorrow before you order, he'll be able to at least tell you what sizing you should get definitely.

I'm running 22.18ext 13.37col up front and 29.78et 17.59col rear with my 6" if that says anything.. Threw on some shock extenders w/ my leveling kit as well. But I'd say you need to go longer
 

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Hey bakdawg good questions on shocks, really key things to be aware of is what size lift you are gonna run. This will be you determining factor in shocks. With that said basic guidelines or mearly using stock sizing goes as follows
Fronts- 11" collapsed 16" extended stroke 4.5"
Rears- 16" collapsed 27" extended stroke 10"

with those figures you can base you shocks. For example running 6" of lift with 35" tires would equate to
Fronts- 14" collapsed 22" extended
Rears - 18" collapsed 30" extended
But here is the kicker of how these figures are made. In the front your increasing travel by 6" by their dropping the arms, bigger knuckles(all depends on the manufactures parts) etc so take the stock figures an add 6" overall to extended length. Now for rears this isnt true, because you are not increasing 6" your adding a 3-4" block so there for add the 3-4 additional inches to your stock shocks. Hope this babbling helps you =)
 

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Discussion Starter #6
Ok, thanks guys. Thats some great info. I will try to get a hold of Nick some time to see what he thinks.
 

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Discussion Starter #7 (Edited)
So it took a while but I finally got new shocks. Went with Bilstein 5125s (5100's just for custom applications). What a pain in the butt of an install. The bushing diameter wasn't the same as the last shocks (rears only) so the bolt wouldn't fit but I did my handyman thing and made it work LOL. Fronts went a lot smoother except for the top bolt holding in both dual shocks. That thing was seized like crazy and took forever to punch out. Barely got everything on before the shop was about to kick me out without my truck for the long weekend. But at last its nice to finally have some shocks in the rear and not have my truck bounce forever after every bump.

Anyways the real reason for the post. I removed the rear shocks first. I started with the bottom mount. When I took the bolt out and pulled the bottom of the shock free they only extended about an 1" to 1-1/2" farther before being fully extended Huh?! WTF??? Thats no good to only have less than 2 inches of extension left in the shock! Thats probably part of the reason the last set went bad.

So the new ones are the same, actually maybe even a bit less due to non-perfect matchup in length as prior brand. So I really don't want to buy a new longer shock and Im definitely not taking the top mount off because of the hell it took to get on there. So Im thinking about welding a shock extender up towards the body of the shocks to compress them about 3 inches. This should put the shock closer to the center of free range and give me closer to 5" of extension. Ill also still have about 6" or more of compression which should be plenty still.

Will this work or am I thinking about this the wrong way?
 
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