Rough Country 3.5 Knuckle Lift Kit

Instructor31 · December 4, 2018

Good evening,

Here’s my 2 cents on the Rough Country 3.5 Knuckle Lift Kit on my 2017 Silverado 1500 Z71. I’ve been driving on it for the past 20k miles and haven’t had an issue. The ride quality is nice, nothing out of the ordinary. I did not option to change the front shocks , just the rear ones.

The lift kit was very easy to install. Key things to watch out for are the front differential drop spacers, they are the most difficult thing to get in place. Also, I’ve seen on other forums that people have been leaving the front diff cooling fins in “thinking” that it won’t need to get cut because it “doesn’t make contact with the cross member.” Yeah.. BS, I thought the same but the cooling find do actually touch the cross member, so make sure to cut them off to avoid miss alignment of your CV axel with your front diff.

Rear blocks and shocks are straight forward, make sure you place the blocks on the correct way with the taper or “ skinny “ end to the front. Measure them out to find that smaller side.

If not you will get shaking while you break at about 25mph and under due to the drive shaft and rear diff universal joints not being at the required angles.

the kit does require a 1/4” spacer for stock wheel, get it, if not you will be rubbing on your upper control arm.

The included Knuckle addresses the upper control arm and CV axel angles. They’re not at an extreme angle, they look like stock angles if not damn near it. I have disassembled my whole suspension again to check the ware on the ball joints and they are still looking good and do not hear any popping sounds from the suspension, or abywhere else for that matter.

If you’re looking at getting your truck lifted and don’t want to break the bank and get some ground clearance, I think this is a very nice option.

https://imgur.com/gallery/5O8DW1V

Edited December 4, 2018 by Instructor31

Tleesmith14 · December 4, 2018

Looks good and this is a kit I am very interested in getting..what size tire did you go with? Did the 1/4 spacer keep all 4 tires in the same track or do the fronts stuck way out like you see with alot of the chevys? You say ride quality nothing out of the ordinary how does it compare to stock? Does your truck sag much when towing?

Instructor31 · December 4, 2018

47 minutes ago, Tleesmith14 said:

Looks good and this is a kit I am very interested in getting..what size tire did you go with? Did the 1/4 spacer keep all 4 tires in the same track or do the fronts stuck way out like you see with alot of the chevys? You say ride quality nothing out of the ordinary how does it compare to stock? Does your truck sag much when towing?

I went with a 285/60/20R. The 1/4 spacer was mostly for clearance since I kept stock wheels. Track is still stock looking, even with the “oversized” tires, I’m still flush with the fenders. It’s been a while since stock but if it means anything, it’s still as smooth, it’s not too rough or stiff. A little depending on load. I chose this kit because I still tow and didn’t want to lose all functionality (torque for the most part).

virtualron1976 · January 30, 2019

I just had this 3.5” knuckle kit put on as well. Rides good, looks awesome.

One issue im researching is if anyone who did this has noticed increased noise or front diff activation when driving in “auto.” The shop that did my install said they are checking with RC engineers, but I haven’t heard back yet. Any thoughts if you have this kit?

TimHortonsJunky · March 29, 2019

On 2019-01-29 at 10:36 PM, virtualron1976 said:

I just had this 3.5” knuckle kit put on as well. Rides good, looks awesome.

One issue im researching is if anyone who did this has noticed increased noise or front diff activation when driving in “auto.” The shop that did my install said they are checking with RC engineers, but I haven’t heard back yet. Any thoughts if you have this kit?

any updates on how these lifts are performing?

2014gmc1500withlift · March 30, 2020

So i installed the rough country 3.5" suspension lift on my 2014 GMC 1500. there really haven't been any problems with it except for one thing. It doesn't happen every time i turn but every once in awhile when i turn my wheel sharply it makes a real small popping sound from my front left wheel. its always the front left wheel and only happens when i turn the same way.

so in short, i turn the wheel sharply to the right and a quiet popping sound comes. not every time. just randomly.

if anyone can help me out that'd be extremely appreciated!!

WilliamBos · March 31, 2020

Looking for updates too. How does ride & handling compare to stock?

WilliamBos · March 31, 2020

On 1/29/2019 at 9:36 PM, virtualron1976 said:

I just had this 3.5” knuckle kit put on as well. Rides good, looks awesome.

One issue im researching is if anyone who did this has noticed increased noise or front diff activation when driving in “auto.” The shop that did my install said they are checking with RC engineers, but I haven’t heard back yet. Any thoughts if you have this kit?

Any updates? I have auto 4x4 too?

NWdirt · April 7, 2020

I have about 15k miles on 3.5" RC knuckle lift. It's been flawless, even after 13 passes at the drag strip. I would say it ride about the same maybe be a little stiffer. I did change RC rear 3" blocks that was in the kit to 2" blocks to make my 2014 LTZ 6.2l level. Just ordered 5100 Bilsteins.

Connor Bain · April 12, 2020

On 4/7/2020 at 11:36 AM, NWdirt said:

I have about 15k miles on 3.5" RC knuckle lift. It's been flawless, even after 13 passes at the drag strip. I would say it ride about the same maybe be a little stiffer. I did change RC rear 3" blocks that was in the kit to 2" blocks to make my 2014 LTZ 6.2l level. Just ordered 5100 Bilsteins.

wow!! that is a really nice truck!.

I have a 2018 Sierra 1500 and really thinking about getting this kit, but all i hear is how trash angles are. reading all this really is making my decision easier to purchase the kit!

Connor Bain · April 12, 2020

On 4/7/2020 at 11:36 AM, NWdirt said:

I have about 15k miles on 3.5" RC knuckle lift. It's been flawless, even after 13 passes at the drag strip. I would say it ride about the same maybe be a little stiffer. I did change RC rear 3" blocks that was in the kit to 2" blocks to make my 2014 LTZ 6.2l level. Just ordered 5100 Bilsteins.

do you have instagram by chance, so i can check out more photos!?

NWdirt · April 12, 2020

5 hours ago, Connor Bain said:

do you have instagram by chance, so i can check out more photos!?

Sorry, I don't. Here's a few more pictures.

NWdirt · April 12, 2020

Mixon87 · March 14, 2021

So I installed on my 2017 Silverado and have the same popping sound from my front drivers side. Has anyone figured out or know why? Also with the three inch block in back I’m not level is still 1 1/2 higher from back to front?

Edited March 14, 2021 by Mixon87

YukonXL04 · March 14, 2021

I have it on my 18, I have no noises. I do feel stiffer than before steering when in 4x4, but I feel some of that is the new tires not slipping as much.

I am about 1.25" higher in the rear. I prefer it as I tow stuff often. And visually it's hard to tell it's not level