Does 275x65x20R require new UCA?

[SilveradoRST]

So I hope I’m asking this question correctly.  I have a ‘19 RST with the GM factory 2” lift kit.  I’m thinking about getting 275x65x20 tires.  I remember when the New Body’s first came out, people who put a 3” lift kit on the front had issues with 4 auto and the stock UCA wasn’t ideal for anything over 2”.  
 

So my question is, by putting on 275x65x20 tires, I’m adding maybe 1/2” to an 1” (I don’t know which for sure.  Correct me here)) of additional height.  This puts me at possibly 3” of lift in total, 1” coming from bigger tires.  Does that mean I should upgrade the UCA?  Or because the extra inch of height is coming from tires and not a lift kit on the suspension, I’ll be ok with the stock UCA?

[richard wysong]

Changing tire size would not affect BJ angle so you should be ok

[Russ757]

Nope. 

[SilveradoRST]

Thank you fellas.  

[Maher Usman]

On 4/4/2025 at 9:09 AM, SilveradoRST said:

So I hope I’m asking this question correctly.  I have a ‘19 RST with the GM factory 2” lift kit.  I’m thinking about getting 275x65x20 tires.  I remember when the New Body’s first came out, people who put a 3” lift kit on the front had issues with 4 auto and the stock UCA wasn’t ideal for anything over 2”.  
 

So my question is, by putting on 275x65x20 tires, I’m adding maybe 1/2” to an 1” (I don’t know which for sure.  Correct me here)) of additional height.  This puts me at possibly 3” of lift in total, 1” coming from bigger tires.  Does that mean I should upgrade the UCA?  Or because the extra inch of height is coming from tires and not a lift kit on the suspension, I’ll be ok with the stock UCA?

You're good with the stock UCA. Tire height doesn't mess with suspension geometry like a lift does. That extra inch from the tires won't hurt anything.