medic_84

I know the OP was asking about the caliper clearance and spacers which the info transient linked is still applicable but just saying that if someone is concerned about UCA clearance this applies as well.

The caliper is not where I was concerned about clearance the tires rubbing against the UCA was my concern. The factory 275/60R20s are very close to the UCA from the factory anything much wider and the outer lugs of the tread could rub under certain conditions. I put the 1/2” hub and wheel centric billet spacers on to compensate for this and have just larger than the factory gap at the UCA.

The problem with going with a wider tire and not using spacers is UCA clearance. 1/2” spacers is ideal…… but if you do not used the longer studs you lose thread engagement and this become dangerous…..

I did concede to not know about Silverados and my apologies to you were sincere at the time. I believe if you read the post you stated my posts were garbage because I was a gmc owner. The exchange between myself and trueblue had nothing to do with you and you chose to insert yourself into it. Yes I did point out you are not a gmc owner here and as you did in the other thread to me. I am sorry.

This gives you an idea of the clearances with the above listed modifications. Please excuse the salt residue from our wonderful DOT team.

Let me preface by saying I do not have a Denali. I have a 22 SLT that I installed an AT4 lift onto. I placed 1/2” pucks on the front essentially giving me 2.5” of lift in the front and 2” of lift in the rear. I also installed Rough Country UCAs. onto the truck do to the fear of factory UCA catastrophic failure. Along with the lift I used hub and wheel centric billet 1/2” spacers……. Wheel studs are from an early 2000s super duty….. yes they fit. Front replacements are Dorman 610-530 M14-1.50 Serrated Wheel Stud - 15.90mm Knurl, 78mm Length, Rear replacements are Dorman 610-490 M14-1.5 Serrated Wheel Stud - 15.7mm Knurl, 69.75mm Length. These front and rear replacement wheel studs are just under 5/8” longer than stock studs. This allows you to have the same thread engagement with the lug nuts as stock. As well as the lift and wheel spacers I had to trim the front fender well. Here is the write up I used for trimming. https://wheelsasap.com/gmc-at4-oversized-tire-trimming-guide/ My tires are 275/65R20 Nitto Recon Grappler. Overall diameter is 34.09” and Overall width is 10.98”. My tires are 3/10 of an inch shorter and 3/10 of an inch narrower than what you are looking at doing. I had to do all of the above to fit my tire without rubbing. The stock 20” SLT wheels and the Denali Ultimate 22” wheels have the same backspacing and offsets.

Didn’t you just get all up in my grill about posting in a forum where the op asked about a Chevy truck and here I find you posting your opinion on a gmc truck. Should I go on about your comments being garbage?

I have no problem admitting when I am wrong see my above post where I concede not knowing anything about Silverados. What I am not wrong about is my experience with the size of the tire on a GMC and you insisting I am. Also to your logic of the Denali Ultimate 22” wheels and tires must be larger than the SLT because the SLT has 20” rims. Again you are wrong….. which shows how little you understand about tire and wheel sizes and how the wheel has little bearing on the over all tire size. The Denali Ultimate 22” wheel and tire combo has an overall height of 32.83” which actually is smaller than the 275/60R20 on the SLT….. wait what!!!! Say it isn’t so!!! But the wheel is bigger!!! Thank you sir for proving my point for me with your own example! But your right my mileage may very. I am not a keyboard commando until people on forums try to tell other people wrong information or unfounded information. Again I did concede that the original op was asking about a Silverado and I have a GMC as Transient pointed out and apparently there may be some differences in body panels that allow for different tire sizes. To that I have no knowledge.

Not quite garbage and not exactly petty. I will concede that I am a GMC owner and can only speak to my experience. My issues lie with other people’s reasoning as to why they are right bypassing all of the evidence pointing to the statements I have made regarding gmc trucks true…… there was a fella on this post who asked me about a 1.5” lift on his elevation and clearing the tire size in question. Then you have this Trueblue a-hole buts in and spouts all kinda nonsense about going from a 17” to 20” rim and that being a 3” increase in size so it must work…… yada yada yada…… I have never claimed to know about Silverados but I did assume it was close. For that I apologize!

Yes! You have missed ALOT!!! You have missed the fact that the 275/60R20 you went to is the stock size he has. Regardless of how much bigger it is than what you had it is still his stock tire. You have also missed that you yourself have said the tire he wants to go to is 1.12” taller or .6” on either side. You have also missed that I put the tire size he wants to put on his truck on my truck and it rubbed. You missed that I had to lift the front of the truck 2” and modify the fender liners to prevent rubbing. Also what you have missed is the 255/70R17 tires you had previously measured 31.09 inches tall and the 275/60R20 you went to measure 32.99 inches tall which is a difference in height of 1.9 inches not the 3 inches you have been claiming. Yes the wheel is 3” bigger but the combo is not. So again I suppose you can continue to argue with me or you can acknowledge you have NOT put the tire size on your truck that he asked about and acknowledge that I may know what I am talking about because I have in fact done the very thing he is asking.

I do not feel like an idiot because I know what I am talking about. You keep speaking to me like I don’t. I know you keep saying it is only a 5% increase but on a non at4 or Trailboss truck it will rub. The reason the example you gave factors in to the 20” being taller is the width of those tires are 245mm so they would be the same width. The sidewall height would be 147mm (60%) of the width. So yes if you add the 147 mm side wall to a 20” wheel vs a 17” wheel then the 20” wheel and tire would be taller. But your statement of the wheel being the same so it has to fit is not correct. And yes you said you went from a 17” wheel and tire to a 20” wheel and tire which yes was bigger but again is the stock size. If the op had an AT4 which he does then the tire would fit. But on his stock truck it will not fit with out rubbing.

I am glad you like speaking to people like they are idiots. Yes you went from a 17” to the 20” but the 20” you went to is the stock size he has now. He wants to go bigger. Wheel size has NOTHING to do with over all diameter of the tire. Yes you have to have a wheel to mount the tire to but the diameter of that wheel has no bearing on the over all diameter of the tire. The width and aspect ratios are what determine the over all diameter of that tire. Back to statement I made before . Theoretically you could have a 15” rim with a 35x12.50 super swamper on it and a 26” wheel with a super low profile tire and the 26” wheel and tire combo may not be any bigger around than the 15” one. The stock 275/60/20 on the non AT4 and Trailboss trucks have very little wiggle room. I am speaking from experience and even posted pictures of the very tire he wants to put in and listed what I had to do to the truck to have the tires fit and yet you still want to argue with me about it and tell me I am wrong.

My statement is still true. the diameter of the wheel has nothing to do with the tire size. He said he went from a 17” wheel to a 20” wheel and gained three inches …… the wheel had nothing to do with it. The difference in tire ratios did. I understand completely how aspect ratios work on tires. My statement was also that I went from a stock 275/60R20 (32.99 x 10.99 inches per Goodyear) to a 275/65R20 (34.09x10.98 inches per Nitto) the Nittos are the recon grappler. My stock Slt was lifted 2” in front and had 1/2” wheel spacers on stock 20” Slt wheels and I rubbed the fender liner, leading to it needing to be altered …. So everyone can speculate all they want but I speak from experience I doubt a 275/65 tire will fit a non at4 or trail boss truck with out modifications