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Posted
31 minutes ago, MTU Alum said:

Cranking the torsion bars doesn't change the spring rate, only the check height so that won't change your ride.

 

I'm not sure the model and tire you are running.  If you have a 18 or 20 inch tire, snow plow prep will bump up your front spring rate two steps (three on reg cabs) and you get the diesel front shock.  If you have 17 inch tires you get the same suspension changes but also about 10 to 15 psi tire pressure increase.  

 

I haven't rode any bilstein shocks before.  A shock can only do so much with higher spring rate.  The higher spring rate not allow you to use full length of travel in compression due to you not having enough mass for that spring rate.

 

I probably would look at a torsion bar change first.  You would have to realign vehicle after the tbar change.  This would lower your FGAWR to 4400 or 4800 lbs from 5600lbs as well.

 

#iworkforGM 

 

I have 18's.  Crew cab.  Any idea on part number for the torsion bars I would need?

 

Maybe I will just mount a couple hundred pounds in iron blocks under the front bumper!  LOL

Posted
7 hours ago, 6.6HD said:

I have 18's.  Crew cab.  Any idea on part number for the torsion bars I would need?

 

Maybe I will just mount a couple hundred pounds in iron blocks under the front bumper!  LOL

Put a winch bumper on it. 

I have a gas crew cab with plow prep. Rides not as bad as I thought, but plan on bilsteins after a court priority add ons.

  • 2 months later...
Posted

Hi Everyone,

I also have the same front stiffness issue on my Chevy Crew 2020 HD 6.6 gas with plow prep. I don'plow.I only tow a 27' toy hauler. Dealer cant tell me what part number i would need to change them to a standard torsion rate. My right side torsion PN #84745487 and the torsion key PN #84634344. Not sure if the bump-stops  are different . mine are PN# 20781438 . I forgot the left side#. need to crawl back under tomorrow.

 

 

Any insight would help.

Steph

Posted

Hello

I have the same 6.6 gas with snow plow prep. 21 HD Denali. Do we need to change the torsion bars and the springs?

Any idea on cost? Has anyone done it and did it make much different in the ride?

 

Thanks

MWK

Posted

Dam, let the salesman talk me into getting the camper/snow plow prep package and now I may regret that decision. I plan on going with fox 2.0 shocks but may have to look into the Cognito comfort torsion bars. I tow a 12K 5th wheel. Will have to see how it rides when I get delivery in 3 weeks. Getting a '21 GMC 3500 AT4.

 

Posted

You should only order the camper package with pickup campers.  You need the higher front GAWR for pickup campers and the higher spring rates for roll.  On diesels, the torsion bar only goes up one size whereas on gas trucks it's two to three sizes.

 

I wouldn't recommend cognito setup.  GM has five different torsion bar rates and there is no way you can replace with one rate like cognito does.  It will probably ride nice but, you could have some handling or roll issues due lack of spring rate.

 

#iworkforGM 

  • Like 1
  • 1 year later...
Posted

Does choosing Z71 suspension over over base Z85 suspension increase front spring rate or FGAWR?

Regards to a 2500hd, 2020+

Posted

No. Only the shocks are different.  The torsion springs for the truck and the FGAWR are set based on the basic truck configuration, then there are two options - heavy duty camper springs (400 lbs higher FGAWR), and plow pkg (400 to 1200 lbs higher FGAWR depending on base configuration). 
 

For my 3500 cclb srw gas, for example, base FGAWR is 5200. I ordered camper springs, which are 5600, and plow package for my truck would be 6000. After a year of driving it I have decided I don’t need the camper springs for my lightweight popup truck camper, which it turns out only adds 100 lbs of load to the front axle, so I just ordered the 5200 torsion bars to modify it back to the base configuration for a little better ride.  I’ll post on how the mod goes in a few weeks. I’m going to get the Autozone loaner torsion bar tool and try it this weekend to make sure it’s the right one for the new trucks. Reviews say it is the right one. 

  • Like 1
Posted (edited)

I've noticed with the VYU Option, when pulling the 5th wheel (14,300 lbs with about 2,400lbs on the pin) that the front end rides pretty high, and the steering is light / less responsive.  Thinking it is most likely higher than it would be with the standard suspension.   I'd venture to guess it would be even more pronounced with a hitch pull trailer, unless the weight distribution bars are cranked down tight.

Just something to consider. 

I'm adding a front hitch, and plan to carry some weight up there to help settle the front end when pulling the 5th wheel.

 

Truck is a CC/SB 3500HD Gas engine. 

Hope this info is helpful.

 

Truck-&-Trailer-Hooked-Up.jpg

Edited by sheath
add picture
  • 2 weeks later...
Posted
On 3/26/2021 at 4:01 PM, MidwestKevin said:

Hello

I have the same 6.6 gas with snow plow prep. 21 HD Denali. Do we need to change the torsion bars and the springs?

Any idea on cost? Has anyone done it and did it make much different in the ride?

 

Thanks

MWK

I just changed my torsion springs from the original heavy duty camper springs I ordered (5600 FGAWR) to the base springs for my model (5200 FGAWR).  I posted a detailed description of the job in the mods subforum. Bottom line it was surprisingly easy, took me 2.5 hours (now that I’ve done it once I could do it again in 90 minutes), and the two new springs cost about $520 shipped plus whatever tax applies.  Autozone loans the special tool you need. See my post for the tool number. 
 

The ride is noticeably a little better, but the big difference is when I go over speed bumps and other large dips and bumps. It’s definitely softer, which is what I wanted. I would imagine going from the 6000 FGAWR bars to the 5200 bars would be a very noticeable improvement in ride with no plow attached. 

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