HELP! New wheels and tires - Truck drives like trash

[TJay74]

1st off tire psi is directly correlated to the load the tire is going to see. If a tire has a load rating of 2000 pounds per tire that means 4 can carry 8k pounds. If the max air pressure on the tire is 51psi that is what is needed when the tire is carrying the max load rating the tire is rated for. 

With that we can formulate:

 

8k pounds equals 51psi (from the manufacture specs for the tire, substitute your actual info here)

5700 pounds (rough curb weight of a 2019 Crew Cab GM truck is 71% of 8k pounds) equals 36psi (or 71% of the max psi rating on the side of the tire).

This is roughly how all manufacture determine the tire pressure that is listed on the sticker on the inside of the door jamb. If it as me I would drop the psi down to the one GM put on the door card and then go from there in adding maybe 1psi when cold until the wear pattern is even across the entire tire. I would also have the alignment checked if it hasnt been and have each wheel/tire re-balanced on a road force balancer. Bear in mind, the biggest the wheel and the bigger the tire the heavier the mass and the more acceptable road force weight the system will allow. They ideally want the road force amount under 20lbs but it isnt always feasible on the bigger truck tires.

[anthony2558]

There must be more going on then the normal air down the tires. I've driven trucks with 7 inches of lift with 37's and never needed to grasp the steering with two hand just to control it. Sounds like you have a crap alignment, or something loose. Or maybe you just have to high of expectations. 

[smrr1]

Those tires dont help at all but do you know if hub centric rings were installed? If not that could be contributing the the bad ride. 
 

I agree to toss the stockers on and see if that fixes it. Otherwise the lift is the culprit.

[ausomecasey]

Following to hear outcome...

[vonrokker]

8 hours ago, ausomecasey said:

Following to hear outcome...

Same, Following to hear the outcome...

[eppieguy]

Speaking from experience here, I'll bet if it was aligned it wasn't aligned properly, or it wasn't aligned at all. Also the high tire pressure will add to the issues you are reporting. I would recommend going to a true front end alignment shop, not a chain store or a dealer, you need someone who will take the time to do a true alignment, not a spec alignment or a toe n' go alignment.

 

Just my .02

[UGADawgs]

I set all my vehicles at 35 cold and they warm up to 37-38 when warm even when the door stickers say 32/34 whether it is an accord, odyssey, outback, or 19 LTZ with 33" goodyear ATs.