Suspension upgrades

You might want to think about the trailer too.

Manufacturers get away with minimum spec. Upgraded spring packs are not expensive & provide great peace of mind.

Upgraded mine from a 6 stack to a 7 stack, longer U bolts, wet bolts & the correct track system which contains HD spring hangers.

Did nothing for the truck but then, as a dually I am well under max ratings.

cmeade wrote:
Don't overlook Bilstein 4600 which are heavier duty depending on your total loaded weight. May not need the sway bar. Recommend the tranny pan even though allisons run cool. Heat is heat. JMHO.

Bilstein 4600 and 5100 are EXACTLY the same shock "except" the 5100 is made for stock and up to a 2" lift.

Unless your truck is lifted, the Bilstein 4600 series, heavy duty yellow shocks will fit and work just fine for your truck.

Thanks for the ideas. I will get back & let you know how I fare.

I have had every generation of GM HD, towing various weights, in some of the country's real backroads. My favorite set up for your truck would be airbags, Bilstein 5100s, or Rancho RS9000s. The 9000s are nice to crank to the high setting when the road is rough.

no need for all the swaybar, trans pan, etc. Save your money.

I too enjoy driving back roads and to make my truck more RV friendly for the heavy loads when the speeds get slow with curves and hills...To keep the truck balanced I installed the 9000 series Rancho Adj shocks for better damping when loaded and to carry that load level for the dips and frost bumps the Firestone rear Air bags with separate shrader valves, Now to control the trans temp better and to keep a eye on it..I put a temp gauge in with the sensor attached to the trans cooler line out to the cooler...Then the line coming back from the cooler I installed a Trans cooler w/Fan a put the fan under the truck bed using HiTemp Hoses in between for the 3' distance and put the control switch for the fan next to the trans temp gauge..works great

jshupe wrote:
Elaborating on what N-Trouble said: If you go buy the recommendations on Duramax forum, either Bilstein or Fox 2.0s all the way around. Air Bags if you need them, but they do negatively impact your unloaded ride quality. I never felt like I needed to do anything about steering when my truck was in stock form, but a steering stabilizer or Cognito PISK3008 is definitely in order with larger tires.

Personally StableLoads made a tremendous difference in overall stability for me, and they are supposed to be able to be disengaged when not in use. In my case the weight of the hitch (240#) and my toolbox (500# or so) on top of them made disengaging impossible, but if that isn't an issue for you, I'd highly recommend them. They were probably the single most impactful modification I made to my truck, possibly even more than the 19.5" tires. I don't recommend riding around with them engaged when unloaded.

The sway bar on a LML isn't nearly as important as on previous generations. The frame is already one of the stiffest out there. Pulling a 14K+ trailer with a stock drivetrain gives me no issues so I wouldn't mess with any of that unless your warranty is out and you just want to.

X2 on the StableLoads. Easy installation and really improve the handling while towing.

Back roads or off pavement? I have bills, next shock will be KYB Monomax.
Additional sway bar could limit off-road articulation.

Are you beefing up the trailer suspension?

Elaborating on what N-Trouble said: If you go buy the recommendations on Duramax forum, either Bilstein or Fox 2.0s all the way around. Air Bags if you need them, but they do negatively impact your unloaded ride quality. I never felt like I needed to do anything about steering when my truck was in stock form, but a steering stabilizer or Cognito PISK3008 is definitely in order with larger tires.

Personally StableLoads made a tremendous difference in overall stability for me, and they are supposed to be able to be disengaged when not in use. In my case the weight of the hitch (240#) and my toolbox (500# or so) on top of them made disengaging impossible, but if that isn't an issue for you, I'd highly recommend them. They were probably the single most impactful modification I made to my truck, possibly even more than the 19.5" tires. I don't recommend riding around with them engaged when unloaded.

The sway bar on a LML isn't nearly as important as on previous generations. The frame is already one of the stiffest out there. Pulling a 14K+ trailer with a stock drivetrain gives me no issues so I wouldn't mess with any of that unless your warranty is out and you just want to.

Don't overlook Bilstein 4600 which are heavier duty depending on your total loaded weight. May not need the sway bar. Recommend the tranny pan even though allisons run cool. Heat is heat. JMHO.