7.5" On Gmt900

FarmerDave · March 12, 2010

Ordered the kit today, made by rough country. Hopefully have it installed in a week......

stlavsa · March 12, 2010

Ordered the kit today, made by rough country. Hopefully have it installed in a week......

good luck what wheels n tires did u decide on?

Edit: Oh just read in the body lift thread your still gonna try n run the stock 18s. Just some insight. Though I am not running that kit, or those wheels, I think you will hit the spindle with the tire.

I have 20x8.5" wheels with a near stock back space on my fabtech kit. (which is about the same height as ur kit if its a true 7.5") I was rubbing the spindle with my tire when I first put the wheels on. They were a 305 width. I ended up with 2" wheel adapters. I put them on all four corners and am very happy. If anything I would have went with 2.5" adapters out back to match the extra width up front.

Honestly without the 2" adapters the truck would look kinda goofy (tall and skinny) the wider look makes the stance so much tougher and more aggressive. 2" on stock or near stock backspace isnt nearly as much as it sounds. I have the pocket style fender flares, and the front tires sit just even with the edges of the flares.. Alot of trucks i see are still way wider of a stance than mine.

On ebay the 1" are the same price as 2" so just a thought. Also I have had the 2" adapters on the truck for over 20K miles now and no problems at all.

FarmerDave · March 12, 2010

Ordered the kit today, made by rough country. Hopefully have it installed in a week......

good luck what wheels n tires did u decide on?

Gonna run 35x12.5 Nitto Trail Grapplers on the stock 18's with a 1/2" wheel spacer for backspacing

FarmerDave · March 12, 2010

Oh really, well that kindof throws a wrench in the mix haha.

I thought about the wider spacers but I am concerned about the load on the bearings. But if you have that many miles on with no problems, thats reassuring.

Well the only other things is, 2 different brands of lifts. I guess how they design it ultimately determines what fits. I think regardless i still wouldn't mind running a spacer just for the stance.

Do you know off hand what your backspacing is on your wheels?

Edit: BTW you have a nice looking truck, hoping mine sits around that height when all is said and done

stefman722 · March 12, 2010

Is the 5" and 7.5" kit for the gmt900 any good? I noticed it says "new" on both. I know the 3" kit has been discussed on here and everyone that installed it had problems. Its a good price for both thats for sure.

FarmerDave · March 12, 2010

Im not sure why they say new, I was quoted probably almost a year ago on a RC 5"

But at that time I had not heard of the 7.5"

Well just from looking at the parts, and what people have told me, its a really good value for the dollar. Clearly not top of the line for that price tho.

Well when i have it in il let you know what i think

stefman722 · March 12, 2010

Im not sure why they say new, I was quoted probably almost a year ago on a RC 5"
But at that time I had not heard of the 7.5"

Well just from looking at the parts, and what people have told me, its a really good value for the dollar. Clearly not top of the line for that price tho.

Well when i have it in il let you know what i think

Yea please let us know..I wouldnt mind purchasing the 5" now and get it installed later on. I already have the 3" bl so 7.5 would be overkill.

jsciaretta · March 12, 2010

I have the newer 3" and its fine.

The reason they say new on the site as far as I know is they dropped the prices for awhile.

I have the emails from RC somewhere the difference between the kits is basically the spacers. The 5" is of course a shorter spacer on the coil spring compared to the 7.5" and the rear blocks as well. You can order leafs if you want you just have to call and its a bit more $$$. If your worried about sag in the rear from hauling i would look into getting some new springs or a different combo cause its a big block in the back.

stlavsa · March 12, 2010

I have the newer 3" and its fine.

The reason they say new on the site as far as I know is they dropped the prices for awhile.

I have the emails from RC somewhere the difference between the kits is basically the spacers. The 5" is of course a shorter spacer on the coil spring compared to the 7.5" and the rear blocks as well. You can order leafs if you want you just have to call and its a bit more $$$. If your worried about sag in the rear from hauling i would look into getting some new springs or a different combo cause its a big block in the back.

I had the same concern with the wider spacers.. but really its no differences than having a wheel with less backspace. Plenty of guys run 4.5inch bs along with a negative offset and they dont tear up bearings or ball joints or anything like that. Like i said I have atleast 20k on mine without any issues.. I use the truck for work, hauling dirtbikes, off-roading, and its my daily driver so it gets used alot.

I believe the backspace is 5.14 on my wheels... with a +18 or 28mm offset so they were tucked in pretty good just like stock. I had the wheels and tires on before I lifted it, which is why i chose that backspace. If I knew I was going to lift the truck 8" i would have with with the 20x10s with 4.5 bs

FarmerDave · March 12, 2010

Well..... I guess the kits are on back order till early april. Must be alot of people buying them. So i wont be able to report my likes/dislikes till then

blackout07 · March 13, 2010

I would take that opportunity to order a different lift. One that drops the diff more than 5" and doesn't require you to cut off the droop stops.

FarmerDave · March 13, 2010

Well after looking at a few instructions for various kits, RC is the only one that doesn't require cutting corners off the diff. Im not really willing to cut part of the drive train up, frame is one thing, welders and steel can restore that. But once you cut a piece off of cast aluminum its never going back on.

Either way.... il be getting the RC for 1300 + labour. A good deal is a good deal.

stlavsa · March 13, 2010

Well after looking at a few instructions for various kits, RC is the only one that doesn't require cutting corners off the diff. Im not really willing to cut part of the drive train up, frame is one thing, welders and steel can restore that. But once you cut a piece off of cast aluminum its never going back on.

Either way.... il be getting the RC for 1300 + labour. A good deal is a good deal.

I was wondering if that 7.5 kit used the same diff drop as the 5" kit. I guess they probably do.. That does kinda suck, but as long as you dont try to use anymore spacers or leveling kits or shit like that you will be alright. Seems to reason that if you were to intall this lift, its going to put you at the same angles as stock truck with a 1.5" leveling kit. ALot of people run those without consequence so i dont see why its going to be a problem. I think the BDS doesnt drop the diff the whole way either and thus justify it by calling it "high clearance".

I dont know much else about the RC kit or its quality, but I dont think that the diff drop is going to be a big deal, although it is nice to retain the stock angles.

FarmerDave · March 14, 2010

Yeah as far as I know the only difference between the 5 and 7.5 is the size of the strut spacers and lift blocks, rest is the same.

I called RC the other day, guy on the phone said 200 kits sold in the first 4 days of March when they started the sale... hes ordered spindles for 600 more, according to him that's the only part they don't have in stock for the kit.