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Discussion Starter · #1 ·
Hi,

I just traded in my '15 SRW long box for a '21 AT4, am sooper stoked.. BUT:

on my new truck the bed rail to 5th wheel clearance is way too tight ! it was marginal on the previous truck and I didn't think it would be that different (doh). Now I cant take my 5th out of my driveway !! Trailer already had axles flipped already has the biggest tires it can on it it can fit and pin box is lowered (which raises the front) as high as it goes... 5th is also on highest setting. And in this config the trailer is already pretty nose up..

So I thought ok, my only options are smaller tires (sacrilidge !) or ?? I fitted a set of 265/65r18 and it added an inch but now the truck looks like a "train truck" (you know, with the skinny little train wheels).. super ghey... so want to go back to bigger tires but what else can I do ? Is removing the lift block a viable option? any other ideas ? I still need to be able to drive in ice/snow/mud when 5th isn't on for work.. so yeah... thanks.

ps no I cant put a hauler body on it I need the box for work...

-Ph
 

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I put 2" lowering shackles on mine. Needs air bags now though
 

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Discussion Starter · #3 ·
on a 2021 3500 AT4 ? who makes those ? it seems way easier to remove the lift block.. and would negate the need for airbags.. but hey I digress I'm a noob to the new HD chassis.. what re the pros/cons of each method on the 20/21 ?
 

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Surprising that the flipped axles don't create enough height; I had to raise my Titanium 5th but did not want to flip axles - I went with the lippert correct track kit which raised it 2" giving me just under 6" of clearance. I had already increased the height of the trailer with larger lt tires a few years ago when I went away from trailer specific tires and was thinking of doing the dropped shackles but did not have to go that direction. These new ones are tall!!!
 

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Discussion Starter · #5 ·
To get it to fit the '15 3500 SWB DBL CAB LB truck I already flipped axles, added 3" shackles off the frame, and dropped the pin, and raised the 5th hitch as high as it would go. On the new truck (same config crew cab), I didn't realize they came 2" higher ! I feel pretty lame. (doh) Its an older '09 so built when trux were small LoL.. aside from my FUGLY skinny train truck tires I really want another way forward..
 

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on a 2021 3500 AT4 ? who makes those ? it seems way easier to remove the lift block.. and would negate the need for airbags.. but hey I digress I'm a noob to the new HD chassis.. what re the pros/cons of each method on the 20/21 ?
HDs are not lifted on AT4 package.

#iworkforGM
 

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Discussion Starter · #7 ·
looking under the leaf springs there is a pad / block there between the spring and the axle ? so you're saying thats common between all HDs, right ? and maybe that cant be removed and the only way is a shorter shackle ?
 

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This is disappointing because I’m looking at lifting my truck a few inches and then get a toy hauler 5th wheel for the future. Will I have issues like this?
 

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Discussion Starter · #9 · (Edited)
ok so I took the wheels off etc. THERE IS NO LIFT BLOCK. what I read on forums as a lift block is actually just on the 1500 and on the HD theres no block its just a part of the spring mount and its integrated, definitely no block. so shackle is the only way ? has anyone done a small drop shackle on an HD 3500 ? any side effects ?
 

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looking under the leaf springs there is a pad / block there between the spring and the axle ? so you're saying thats common between all HDs, right ? and maybe that cant be removed and the only way is a shorter shackle ?
Yes, all 2020/2021 HD's are the same height.

In the 1500 series, the gmc AT4 and the chev Custom Trailboss and LT Trailboss each have a 2 " factory lift.


Yes, the 20/21's HD's are taller than the previous generation.
And fwiw, the new HD's are taller than the 'factory lifted' 1500's.
 

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Discussion Starter · #11 ·
ok got it. so anyways, its a very real problem.

I have 5 trailers too (all for work) so I need to figure this out ! Was only honestly really worried about my big 5th but I'm gonna have clearance issues on the gnecks /w decks too...

Only option I am seeing right now is putting super lame 265/65-18s on and having er look like a "train truck" (you know, those ones that run the tracks with super skinny pizza cutter tires).. that would drop er an inch or so...

shackle ??
 

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I looked into the shackles when I first received my 20 AT4 short box before going with the Lippert solution. It looks to be a good solution and in my opinion lowers a truck I feel is too tall, I would sure look into that first. JMO
 

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The lippert correct kit is for the trailer only and in my case raised my trailer approx. 2 inches, I didn't word that reply very good but I had also looked at the lowering shackles if I needed it and had asked others who may have installed those shackles and how it effected their trucks. None had reported any adverse affects from it but in the end I did not have to go that route.
 

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2020 Silverado 3500 LT SRW Crew cab Duramax
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Watching this thread ...

Coming from a 2004.5 Ram 3500, this new truck is 3" taller. My fifth wheel is already flipped. But,I thought I was going to have a bigger problem with it than I actually have. First, the squat from the trailer's pin weight was more than I thought it would be. That helped a bit. Second, I have an Andersen Ultimate Hitch which moves the kingpin back about 9". That reduces the amount of the trailer overhang that's actually over the bed of the truck. I have about 6" of bed clearance and the trailer rides just a bit nose up. I can live with it the way it is but would love to lower the truck a few inches to make it easier to get in/out and access stuff in the bed.
 

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What 5th wheel hitch are you using?

We recently ordered a 5th wheel toy hauler to tow with our 2020 AT4 HD. I have the 6'9" bed.

The hitch I'm decided on is the B&W RVK3710, which is for the 2020+ puck systems. Now you have me concerned about height of the hitch and 5er to rail clearance.

I was looking at the Andersen Ultimate Hitch but have decided against it. My understanding for it though is that Andersen has released a new version that is slightly taller to accommodate the higher bedsides.
 

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Discussion Starter · #18 ·
I have 2 hitches I've tried em both at max height, bed hitting doghouse when I do over the crown on my driveway... looking at lifting the trailer with lift blocks (!) cant really think of anything else I haven't done, short of lowering the truck which I really dont wanna do ..
 

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on the 2011 to 2015 ( not sure on newer trucks) , the 3500 when lowered causes interference with overload springs hitting the stops when driving unloaded. which is a real pain in the ass-literally and figuratively. I took the hangers out and added airbags to get cargo capacity back. looks better, fits my 5er without mods.
 

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I have 2 hitches I've tried em both at max height, bed hitting doghouse when I do over the crown on my driveway... looking at lifting the trailer with lift blocks (!) cant really think of anything else I haven't done, short of lowering the truck which I really dont wanna do ..
I feel your pain. I'm new to 5th wheel towing, and trying to figure this stuff out makes my brain hurt! Our 5er that we ordered is already at 13'6". No option to raise it any taller without causing all sorts of clearance issues with overpasses, etc.
 
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