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Posted (edited)

I need concrete facts as there is so many conflicting answers, data, etc. I have a 2020 Sierra SLT with stock 20" wheels and OEM 275/60R20's (33's). I want to level the front 2", continue to use the stock 20" wheels but upgrade the tires to 285/60R20's and replace the UCA's with aftermarket ones and not have to use wheel spacers or do any trimming or cutting. 

 

Cognito says I need spacers.

Zone says I need 1.5" spacers. Really? 1.5"? This makes no sense as even my OEM tires wouldn't even work then. 

BDS says it "should" fit. 

 

Am I stuck with having to use 275/60R20's? Will aftermarket UCA's even work with my stock wheels regardless of tire size? Anyone running my same setup with aftermarket UCA's? 

 

 

 

 

Edited by Weiser699
Posted

I have a stock 21 1500 AT4 and put on 285/60/20 cooper at3 xlt,  0 rubbing using factory wheels, no wheel spacer

Posted

yes all stock if you search some on this sight you will see that all the 19-21's have the same upper control arms you don't need aftermarket ones  unless you go more than 2" on factory slt 1500

Posted

So AT4's use the exact same UCA as a regular SLT/SLE, etc? Same part#? I am going to get no additional wear and tear on my UCA's if I stay 2" or less? I hear horror stories of owners of the new model GM's/Chevy's destroying a UCA even with a 2.5" level and that the OEM UCA's are basically junk. Most manufacturers of level's recommend new UCA's because of this every reason. I just can't imagine why aftermarket UCA's are so significantly "beefier" than stock that any tire size over OEM requires a spacer or different wheels. 

Posted

the  problem is when you go higher than 2".   Had 2" on my 2014 60,000 miles still drove like new when I traded it in.  I really suggest you go to the silv/gmc mods section and read a crap load of info there. Most guys with trouble are raising their trail boss or AT4 higher without the UCA's

Posted (edited)

Or buy the factory 2" lift and have a competent mechanic install it.  Look at the gm kit no control arms included, should speak for itself

Edited by 81mmcat
Posted
4 minutes ago, 81mmcat said:

Or buy the factory 2" lift and have a competent mechanic install it.

GM won't install a factory 2" lift because I have the max tow package (NHT code) plus it still has the crappy Rancho's so I am just going to do Bilstein coilovers in the front and bilstein rear shocks with a 1" block instead.  

Posted (edited)
4 hours ago, 81mmcat said:

the  problem is when you go higher than 2".   Had 2" on my 2014 60,000 miles still drove like new when I traded it in.  I really suggest you go to the silv/gmc mods section and read a crap load of info there. Most guys with trouble are raising their trail boss or AT4 higher without the UCA's

 

On the current trucks that is correct, that is incorrect on previous gens. I am not sure how 2" became some magic go no go zone but on previous gens the UCA's weren't designed to be run lifted from the factory, so anything over factory accelerated the wear and how much was determined by how big or heavy the tires were, where you drove, how much over factory lift you went, etc. Many had no issues, but also many didn't keep them long enough to see wear (60k won't be a good indicator) or most of the time were street queens that never saw any off road driving or towing/hauling. The current gens UCA's were designed to work stock and with the 2" level from the factory TB/AT4 lift, but again anything over that accelerates wear and those that add another 2" are having big issues which they effectively are stacking 4" of leveling kits on. I personally would stop at 2". My current 2014 has a modest 1.25" level up front and 1" rear knowing it adds wear to the front end and UCA's but not as bad as those running 2" or more. So far at 90k they have been good even with a few thousand miles of off road driving and some towing and hauling thrown in too. I also just run factory wheels and P-rated tires though too, heavier tires speed up the wear process on much of the front end. 

 

As you said though Bilstein level under 2" sounds like a great plan...

 

Tyler

Edited by Amcguy1970
Posted
15 minutes ago, Amcguy1970 said:

 

On the current trucks that is correct, that is incorrect on previous gens. I am not sure how 2" became some magic go no go zone but on previous gens the UCA's weren't designed to be run lifted from the factory, so anything over factory accelerated the wear and how much was determined by how big or heavy the tires were, where you drove, how much over factory lift you went, etc. Many had no issues, but also many didn't keep them long enough to see wear (60k won't be a good indicator) or most of the time were street queens that never saw any off road driving or towing/hauling. The current gens UCA's were designed to work stock and with the 2" level from the factory TB/AT4 lift, but again anything over that accelerates wear and those that add another 2" are having big issues which they effectively are stacking 4" of leveling kits on. I personally would stop at 2". My current 2014 has a modest 1.25" level up front and 1" rear knowing it adds wear to the front end and UCA's but not as bad as those running 2" or more. So far at 90k they have been good even with a few thousand miles of off road driving and some towing and hauling thrown in too. I also just run factory wheels and P-rated tires though too, heavier tires speed up the wear process on much of the front end. 

 

As you said though Bilstein level under 2" sounds like a great plan...

 

Tyler

Thanks Tyler. Yes, my plan is to do either 1.75-2" max in the front with those Bilsteins as I will be doing a 1" block in the rear. I still want to maintain about a 3/4-1" rake so once I have my Bilstein monotubes and 1" block in the rear installed will determine how much front lift I'll need. If the UCA's on these SLT's are the same as the AT4s, then I think I'll be safe with 2". I don't plan on off-roading much at all, mostly highway travel and occasional towing. 

Posted (edited)

I have Bilstein AT4 lift on my 21 elevation ( 3in front and 2in rear).....have a cognito UCA and stock wheels..everything fits and works fine......whatever the stock 20s are on elevation is what i have....

 

i bought the cognito becasue it fit with stock wheels

 

and 3 people had broken TB arms leveling those but thats 4inches and way too high for stock arm....i am in the middle and didnt want any problems so its cheap insurance and plus the angle makes truck ride better without binding......not to mention its a much beefier unit anyway and if i offroad it i would want something more stout than stock ones ( when you see them off the truck they look like they were made from a coke can seriously)

 

UCAs typically have a 2" range for height they are made for,......if at stock TB height you wont have or shouldnt have any issues....

 

another thing i like is ball joint beefy and is replaceable.....its bolted on so when they wear out just buy a new ball and bolt it on....

 

 

Edited by Dunn
Posted

I know it is not a Sierra, but I have a 2020 LTZ Z71. I had Bilstein 6112's installed up front set at 2" lift. I am running the stock UCA's, Toyo 285/60/20's on Fuel Sledge wheels, 20x9 +19 offset. I believe the Factory 20x9 wheels were +28 offset.

 

No rubbing or trimming.

 

Good luck.

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