GM 2 Inch lift vs 2 inch front and 2 inch rear blocks

jordanl010 · September 12, 2019

Hey All,

Been on the forums for about a month now and have been doing a ton of digging into anything I have been trying to do. So far these forums have been a huge help. One question I had however is doing the 2 inch GM lift from the dealer or just adding a 2 inch lower mount spacer and a 2 inch rear block.

How much is the GM lift really giving you that helps out with angles and helping out the suspension life with their kit? If I were to just get a 2 inch front spacer and a 2 inch rear block, I would achieve the same but would I run into quicker suspension wear with that route down the line? I have no problem with going toward the GM route but understanding that I can get the same look with less money I just wanted to try and get peace of mind of knowing if I do something that isn't the GM lift, will it really cause premature issues?

I have the 2019 GMC Sierra SLE. So not factory lift or anything like that.

UGAreb · September 12, 2019

Been wondering the same thing myself! Following for responses....

SatinSilvy · September 12, 2019

With the GM lift you’re getting new CV Axles to help with the angles. I’m wondering how much and if GM has them for sale as “replacements” yet. If that’s the case you could just do a 2” spacer lift and the longer CV’s. Also I read that no matter who installs the GM factory trail boss lift that your warranty is still good. So therefore you and your buddy can install it and still be covered. The other thing that GM offers is recalibrated powersteering, Speedo and front parking assist sensors.

jordanl010 · September 12, 2019

9 minutes ago, SatinSilvy said:

With the GM lift you’re getting new CV Axles to help with the angles. I’m wondering how much and if GM has them for sale as “replacements” yet. If that’s the case you could just do a 2” spacer lift and the longer CV’s. Also I read that no matter who installs the GM factory trail boss lift that your warranty is still good. So therefore you and your buddy can install it and still be covered. The other thing that GM offers is recalibrated powersteering, Speedo and front parking assist sensors.

Thanks for the info. I knew about the warranty and that is definitely a plus. I see a bunch of people on here tossing on spacers and pucks that are usually 1.5-2" tall. So I am wondering if it really is worth going to the GM lift if others are just doing 1.5-2" spacers and IF that is really not much of a concern on the suspension geometry and lifetime.

SatinSilvy · September 12, 2019

I personally just broke down and ordered a 2” rough Country level last night. I’m waiting for Fox to release their coil over set up late November. I just can’t stand the factory rake and want to lift the front up. I have 35’s ready to go so I’m gonna see if I can squeeze them in with a level.

I figure the stock tires are sitting at 32’s, the 35’s are measuring out to 34” so 2” level should accommodate a 2” taller tire I hope!

amxguy1970 · September 12, 2019

29 minutes ago, SatinSilvy said:

I personally just broke down and ordered a 2” rough Country level last night. I’m waiting for Fox to release their coil over set up late November. I just can’t stand the factory rake and want to lift the front up. I have 35’s ready to go so I’m gonna see if I can squeeze them in with a level.

I figure the stock tires are sitting at 32’s, the 35’s are measuring out to 34” so 2” level should accommodate a 2” taller tire I hope!

Then those aren't 35's. That is like saying you are 6 foot and only being 5'11"...

Tyler

SatinSilvy · September 12, 2019

10 minutes ago, amxguy1970 said:

Then those aren't 35's. That is like saying you are 6 foot and only being 5'11"...

Tyler

No “big tire syndrome” here trust me. I picked up a set of used 295/65/20’s, not sure what they measured out brand new but now they are sitting at 34” without rim/air. So I’m hoping that these will fit once I install the leveling kit.

f8l vnm · September 12, 2019

295/65/20 is for sure a 35 in tire .

https://www.tacomaworld.com/tirecalc?tires=295-65r20-285-65r20

Ezekiel2517 · September 12, 2019

Yup. Because, math.

295mm x 0.65 x 2 sidewalls / 25.4 mm/in. = 15.09 in" sidewall + 20" rim = 35.09" tire

Unless its a BFG A/T, then take a half inch off. They must be bad at math.

Edited September 12, 2019 by TexasGMCZ71

FiatDale · September 12, 2019

Good stuff in this thread. I keep going back and forth with this myself. What’s funny is nobody seems to mention the added stress on the ball joints with the level. Even with the GM kit, it does nothing for the ball joints, only the CV.

Ezekiel2517 · September 16, 2019

The rough coutnry kit comes with new A-arms that fix the ball joint stress, but it does not come with the new CV axle. I am intersted in the RC 3" kit, but it has a lot of cutting that has to be done on the crossmembers. If something goes wrong and I need to remove it for warranty that is a no-go.

Now I am also wondering if a 2-2.5" front spaver and a 1" rear block would just be easier and good enough.

I called Billstein to ask about 5100s and they said not before the first of the year.

AJMBLAZER · September 17, 2019

I am sort of wondering if GM designed the suspension to be able to have that extra lift stock. It would be cheaper for them in the long run if they could use the same suspension components on the Trail Boss and AT4 as a regular 4 x 4 got. Also, considering the amount of people who buy a new truck and immediately level it nowadays that is something they could consider in their sales design. I would bet money the reason the wheel openings are a lot bigger on this generation is to fit bigger tires like Ram and Ford could.

tanner709 · September 17, 2019

21 hours ago, TexasGMCZ71 said:

The rough coutnry kit comes with new A-arms that fix the ball joint stress, but it does not come with the new CV axle. I am intersted in the RC 3" kit, but it has a lot of cutting that has to be done on the crossmembers. If something goes wrong and I need to remove it for warranty that is a no-go.

Now I am also wondering if a 2-2.5" front spaver and a 1" rear block would just be easier and good enough.

I called Billstein to ask about 5100s and they said not before the first of the year.

the rough country kits are horrible. I'd advise to stay away. They are cheap for a reason

In saying that, almost all "lift" kits will require cutting or trimming, adjustment of the x-fer case, and cross member mods. If you wanna go up, you'll most likely have to do permanent mods to your truck that will also most likely void warranty.

Some dealers, even aftermarket installers, will provide warranty with installation - for a cost.

It's one of those things if you commit, you should at least buy quality parts to support it IMO.

tanner709 · September 17, 2019

14 hours ago, AJMBLAZER said:

I am sort of wondering if GM designed the suspension to be able to have that extra lift stock. It would be cheaper for them in the long run if they could use the same suspension components on the Trail Boss and AT4 as a regular 4 x 4 got. Also, considering the amount of people who buy a new truck and immediately level it nowadays that is something they could consider in their sales design. I would bet money the reason the wheel openings are a lot bigger on this generation is to fit bigger tires like Ram and Ford could.

people complained for 20+ years about square wheel wells. and GM still has a trapezoid shape. Most likely designer changes brought the new look, while still trying to keep the classic theme overall.

They still sold trucks regardless of this complaint. One of the highest sellers too - so I doubt there was much influence.

Edited September 17, 2019 by tanner709

Ezekiel2517 · September 17, 2019

2 hours ago, tanner709 said:

the rough country kits are horrible. I'd advise to stay away. They are cheap for a reason

In saying that, almost all "lift" kits will require cutting or trimming, adjustment of the x-fer case, and cross member mods. If you wanna go up, you'll most likely have to do permanent mods to your truck that will also most likely void warranty.

Some dealers, even aftermarket installers, will provide warranty with installation - for a cost.

It's one of those things if you commit, you should at least buy quality parts to support it IMO.

Ive never had a full lift installed before. What makes the Rough Country Kit bad? It seems like its really just a fancy level kit with a few extra bells and whistles.