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Discussion Starter #1
I think I've decided that I would like to install a 4" suspension lift on my 2018 2500HD; would like to run a 285/65-20 tire for mostly dirt road type driving/some trails and keep 5th wheel towing abilities; possible? Which lift seems to be the best engineered and most dependable? Anyone have experiences towing a 5th wheel with a 4" lift/larger diameter tires and stock gears?

Thank you!
 

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If you want quality, go with BDS or Fabtech. I have the Fabtech 4 inch suspension lift kit with the medium grade shock option and 35 inch tires (285/75/18) on my 2019 Chevy 3500HD High Country. Very happy with this combination. My truck now looks like a “real“ truck next to a Ford Super Duty ... and constantly gets compliments on how good it looks. I tow a 10,000 lb bumper-pull travel trailer all over the western states during camping season. Now the honest downsides. You will lose some of your bottom-end and the ability to properly tow in 6th gear unless you change your ring and pinions to compensate for the larger tires. My truck now tacks the same RPM in 5th gear at highway speed as it did in 6th gear before the lift and tires ... so it’s like I lost a gear towing at highway speeds ... now have a 5-speed. Also lost about 1 to 2 mpg around town and 2 to 3 mpg on the highway. Not complaining ... I expected all of this when I put the lift and tires on (not the first lift I have put on, so I knew what to expect). I highly recommend installing the Hypertech inline calibrator that corrects your speedometer, and more importantly, corrects the shifting points (installed mine at the same time as the lift). I also put a Banks Derringer, cold air intake, and DPF-back exhaust on my truck ... so my truck does a little better with the extra horsepower and torque. Note that the Fabtech and BDS lifts come with very little rake ... so I highly recommend getting air bags with the spacers for the lift (I have the Airlift wireless air bags with 2 inch spacers). My truck sits perfectly level with or without a load ... the way it should be. I personally place 1000 lbs of sand bags in the back of my truck when not towing and run my air bags at 30 psi to make it sit level ... but more importantly ... with this setup my truck rides like my old half-ton pickups. Honestly ... my truck rides better with the 4 inch lift and 35 inch tires. One last thing ... broke my stock idler arm due the stress of turning 35’s. So I replaced the idler and pitman arms with Kryptonite‘s heavy duty sealed bearing design (no more GM ball stud junk design). Hope this helps ... it took many hours late at night in my garage over the last year getting this truck setup right with a lift ... but she is bullet-proof now. Hope this helps.
 
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Discussion Starter #3
If you want quality, go with BDS or Fabtech. I have the Fabtech 4 inch suspension lift kit with the medium grade shock option and 35 inch tires (285/75/18) on my 2019 Chevy 3500HD High Country. Very happy with this combination. My truck now looks like a “real“ truck next to a Ford Super Duty ... and constantly gets compliments on how good it looks. I tow a 10,000 lb bumper-pull travel trailer all over the western states during camping season. Now the honest downsides. You will lose some of your bottom-end and the ability to properly tow in 6th gear unless you change your ring and pinions to compensate for the larger tires. My truck now tacks the same RPM in 5th gear at highway speed as it did in 6th gear before the lift and tires ... so it’s like I lost a gear towing at highway speeds ... now have a 5-speed. Also lost about 1 to 2 mpg around town and 2 to 3 mpg on the highway. Not complaining ... I expected all of this when I put the lift and tires on (not the first lift I have put on, so I knew what to expect). I highly recommend installing the Hypertech inline calibrator that corrects your speedometer, and more importantly, corrects the shifting points (installed mine at the same time as the lift). I also put a Banks Derringer, cold air intake, and DPF-back exhaust on my truck ... so my truck does a little better with the extra horsepower and torque. Note that the Fabtech and BDS lifts come with very little rake ... so I highly recommend getting air bags with the spacers for the lift (I have the Airlift wireless air bags with 2 inch spacers). My truck sits perfectly level with or without a load ... the way it should be. I personally place 1000 lbs of sand bags in the back of my truck when not towing and run my air bags at 30 psi to make it sit level ... but more importantly ... with this setup my truck rides like my old half-ton pickups. Honestly ... my truck rides better with the 4 inch lift and 35 inch tires. One last thing ... broke my stock idler arm due the stress of turning 35’s. So I replaced the idler and pitman arms with Kryptonite‘s heavy duty sealed bearing design (no more GM ball stud junk design). Hope this helps ... it took many hours late at night in my garage over the last year getting this truck setup right with a lift ... but she is bullet-proof now. Hope this helps.
Thank you for the detailed response, very much appreciated; especially the extra details. The lift kits I've been researching are BDS, Fabtech, Cognito, CST and RCD. I've watched as many online videos as I can find but prefer 1st hand experience over youtube. When I was still active duty I remember all the HD trucks the Navy outfitted for more than street use were equipped with the RCD lift (doesn't seem to be as popular these days). I did see both the Fabtech and BDS kits use 1/4" steel which I like.

If you don't mind my asking, what made you go with the Fabtech over other kits?
 

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I had Fabtech’s 3.5 inch UCA kit and hated it. Not Fabtech’s fault, it is probably the most complete high quality leveling kit, but it ruined my ride and was hard on my CV joints at those angles. Fabtech offered a deal where they credit the full amount of the UCA leveling kit towards the full suspension lift kit. Could not go wrong with that exchange / upgrade program. Plus Fabtech stands behind their products regarding warranty claims.
 

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Discussion Starter #5
I had Fabtech’s 3.5 inch UCA kit and hated it. Not Fabtech’s fault, it is probably the most complete high quality leveling kit, but it ruined my ride and was hard on my CV joints at those angles. Fabtech offered a deal where they credit the full amount of the UCA leveling kit towards the full suspension lift kit. Could not go wrong with that exchange / upgrade program. Plus Fabtech stands behind their products regarding warranty claims.
Can't beat that deal. Good info on the steering upgrades; looks like this will be a multiple day install for sure!
 

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Discussion Starter #7
I was taking some wheel measurements (I'm 100% stock for now) referencing the fender wells and found the rear wheels are 18mm (per side) inboard the outer top fender edge and the fronts are darn near flush. I remember this being the case on my 05 2500HD as well; although I think it was 25mm or 1" each side back then. I ended up going with a staggered wheel setup with the rears having 1" less backspacing on the 05....turned out real nice.

That's my long way of saying I pretty sure I'm going to go with a +18mm offset up front and a 0 offset in the rear....should have a similar result.

Couple of pics of my old HD



 

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I was taking some wheel measurements (I'm 100% stock for now) referencing the fender wells and found the rear wheels are 18mm (per side) inboard the outer top fender edge and the fronts are darn near flush. I remember this being the case on my 05 2500HD as well; although I think it was 25mm or 1" each side back then. I ended up going with a staggered wheel setup with the rears having 1" less backspacing on the 05....turned out real nice.

That's my long way of saying I pretty sure I'm going to go with a +18mm offset up front and a 0 offset in the rear....should have a similar result.

Couple of pics of my old HD



I was taking some wheel measurements (I'm 100% stock for now) referencing the fender wells and found the rear wheels are 18mm (per side) inboard the outer top fender edge and the fronts are darn near flush. I remember this being the case on my 05 2500HD as well; although I think it was 25mm or 1" each side back then. I ended up going with a staggered wheel setup with the rears having 1" less backspacing on the 05....turned out real nice.

That's my long way of saying I pretty sure I'm going to go with a +18mm offset up front and a 0 offset in the rear....should have a similar result.

Couple of pics of my old HD



All 4 of my wheels are +18mm offset (front & back). Stock wheels are +44 offset. This means my aftermarket wheels stick out 1 inch farther than the stock wheels on each side of the truck.

If you stand behind my truck and squat down, the front and back wheels appear to line up perfectly.

I have also noticed that the front and back wheels line up differently regarding the upper wheel well body line. (my front wheels stick out 18 mm and the back are near flush).

This leads me to believe the front and back wheel well body lines do not match up ... the back sticks out farther than the front.

So you may want to double check before purchasing different front & rear wheel offsets (however, I do know what you are talking about because my 1999 3/4 ton Chevy had a wider front stance than the rear).

Best way to double check which of us is correct, use a 2 ft level and plumb mark the ground for all 4 tires. The distance between the front tire marks and the distance between back tire marks should be the same or different. Let me know because I am interested how it works out. I have been wrong before.
 

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Discussion Starter #9
A quick search (could be wrong) shows front track width at 68.8” and rear track width at 67.3 inches.
 

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Chevys are notorious for this. It's a side effect of IFS. I wouldn't get different offset rims, just get a small set of spacers for the rears if it bothers you that much. The spacer game has changed and they are reliable now. I've put mine old ones through hell and back twice and had 0 issues.
 

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Discussion Starter #12
thank you, what I need to try and find out is, is the rear track width the same for both the 10.5 AAM and the 11.5 AAM rear diffs. That measurement I found did not specify; could be same for both but I don't want to assume.

As for running spacers, I do plan on towing a fairly large RV and while I'm not a doom and gloom guy when it comes to spacers I'm wondering if a staggered wheel might be a better choice? The only downside to going staggered is I could only rotate side to side. My other factor is I live in Nevada, very dry/hot climate, certain things are only reliable for 2 years; batteries being one of them and from what I can tell tires as well.....my stockers (Michelins) are already just starting to develop fine cracks (again towing and reliability are my biggest considerations). In my estimation, tire rotation is the lower consideration because the tires don't last much beyond 2 years (that I'm comfortable with anyway)

With that said, I've seem a bunch of pics of trucks with non staggered wheels (internet pics) and its seems real tough to even notice the difference.
 

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I dont know you personally so i cant dissuade you either way. I can tell you this though - my old truck was an 03 1500 with the 5.3. I built the motor, had 420 tq to the wheels dynod with 36 toyo MTs on it. Many a burnout. Decent amount of mud and rock wheeling. It even barrel rolled down a hill (unattended) and no issues with the spacers. I actually managed to grenade the g80 without any issue to the spacers.

As long as you keep everything torqued to spec there should be no issues. But you do you booboo

The only way youll actually notice is if you look from the corner of the rear bumper towards the front of the truck. Itll bother your OCD more than anyone even noticing
 

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Discussion Starter #14
I dont know you personally so i cant dissuade you either way. I can tell you this though - my old truck was an 03 1500 with the 5.3. I built the motor, had 420 tq to the wheels dynod with 36 toyo MTs on it. Many a burnout. Decent amount of mud and rock wheeling. It even barrel rolled down a hill (unattended) and no issues with the spacers. I actually managed to grenade the g80 without any issue to the spacers.

As long as you keep everything torqued to spec there should be no issues. But you do you booboo

The only way youll actually notice is if you look from the corner of the rear bumper towards the front of the truck. Itll bother your OCD more than anyone even noticing
That makes two of us that have grenaded a G80! My 05(above) had a detroit locker in it because of that! Thanks for info brother!
 

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Look up far from stock spacers & whistlin diesel on youtube. The guy is a goober but stacks wheels spacers on his duramax and powerstorke and beats the hell out of his trucks. The suspension breaks and the spacers have yet to fail.
 

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Discussion Starter #16
any thoughts on upgrading any steering components with the 295/60-20 tire?
 

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Discussion Starter #17
I thought I was sold on a 4" lift but after research upon research I've ultimately decided against it. Going to lift the front 2", put some larger tires on it, upgrade whats needed and call it done.

Leaning heavily towards the suspensionmaxx full kit; appears to be the most complete and well thought out.
 

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I thought I was sold on a 4" lift but after research upon research I've ultimately decided against it. Going to lift the front 2", put some larger tires on it, upgrade whats needed and call it done.

Leaning heavily towards the suspensionmaxx full kit; appears to be the most complete and well thought out.
Make sure to look at Fabtech’s 3.5” kit. It is the most complete leveling kit I have found. It comes with aftermarket knuckles to return upper and lower ball joints plus ties rod ends to the proper factory angles. It was the only leveling kit that offered aftermarket knuckles when I purchased for my truck. And Fabtech has a trade-up program where they will give you full credit of the leveling kit towards a lift kit if you do not like the leveling kit. I did not like the stiff ride with my torsion bars cranked up 3 inches to fully level my truck ... so I traded up the 4 inch lift kit and got my soft ride back ... no regrets.

 

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Discussion Starter #19
Make sure to look at Fabtech’s 3.5” kit. It is the most complete leveling kit I have found. It comes with aftermarket knuckles to return upper and lower ball joints plus ties rod ends to the proper factory angles. It was the only leveling kit that offered aftermarket knuckles when I purchased for my truck. And Fabtech has a trade-up program where they will give you full credit of the leveling kit towards a lift kit if you do not like the leveling kit. I did not like the stiff ride with my torsion bars cranked up 3 inches to fully level my truck ... so I traded up the 4 inch lift kit and got my soft ride back ... no regrets.

I did not realize their kit came with knuckles; bet that helps a great deal with bump steer. Thank you for the link!

Side note; I took my truck out on some dirt trails and the front felt under sprung to me, pogo much!
 

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I did not realize their kit came with knuckles; bet that helps a great deal with bump steer. Thank you for the link!

Side note; I took my truck out on some dirt trails and the front felt under sprung to me, pogo much!
GM and other manufacturers seem to lean toward the under-sprung side to offer a more comfortable ride when unloaded. This unfortunately causes the suspension to bottom-out for those of us that actually fully articulate our suspension off-road. To help deal with this I slightly cranked up my torsion bars where I can slip a piece of paper underneath the jounce bumpers and the stop, instead of the recommended factory setting of the jounce bumper slightly resting on the stop. This added a little stiffness to the front suspension, but nothing like when I cranked the front end up 3 inches with aftermarket keys that reindexed the torsion bars. That was so stiff you could feel the teeth rattle in your head when you hit a pothole in the road.

If you end up going the Fabtech direction, I cordially recommend staying away from their cheap Perfomance shocks, they are $50 junk. I have the Fabtech Stealth shocks on my 4 inch lift and Fabtech did an excellent job valving these monotube shocks specific to our truck, and most importantly, they are affordable ($100 shock).

If you want the ultimate front suspension setup (my opinion) ... go with the BDS 2-3” Coilover Conversion Lift Kit. The ultimate rear suspension (again my opinion) would be a Kelderman air suspension setup that deletes the leaf springs. I almost went this direction, but since I update my trucks every few years, I couldn’t justify spending this much on a lift kit. Total for this setup was about $10k for both kits.

Best of luck regarding whichever kit you end up going with.

Side Note: Personally, if I could do it all over again, I would have cranked the stock torsion bar keys up 1 inch in the front and installed a set of Sulastic Shackles with the 1.5 inch drop kit in the back. Then I could have avoided all the expenses and issues inherent with leveling and lift kits. But I do gotta admit it feels good being at eye level with the Fords and Dodges, especially driving the better looking truck 😉.
 
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