I am wanting to go a smidge higher on my lift but am getting a little close to the garage door mechanism in my low ceiling. I think it will fit but wanted a second opinion as I like keeping my truck in the garage when its 0 degrees out there. I have about 3 and 1/4 inches of room to work with before the roof rack hits parts of the garage door mechanism on the ceiling.

Current setup: Bilstein 5100 at .85 up front, 265/65/17 tires.

Planned setup: Bilstein notched up to 1.75, add 1.5 rear spacer, 265/70/17 tires.

I calculate I'll gain .5 on the tires and 1.5 for the spacer, so I'm at 2 for the roof rack clearance.

Will this plus the front lift still keep the top of the vehicle within my 3 inch limit? I know the front lift is usually double what you put in there, but I only care about measuring the roof of the truck and not the wheel well clearance.

Thanks!

So sounds like for the front you'll add 1.8" (lets call it 2") + .5 =2.5" and in the back 1.5" + .5" = 2" higher than you are now.
Try this: put 2.5" of wood (or similar) in front of front tire, 2" in front of rears and drive up on it. Then check how much clearance you have left (do it slow & in 4Lo & have someone watch!)
Don't know if you get snow where you are but remember this: an issue I have is snow build up OUTSIDE the garage gets compacted and now I'm driving in higher that I normally would be. Does that make sense?

Makes sense to me! Great idea with the wood blocks- I'll give it a go...SLOWLY

This just happened to me with the recent snow storm. There are now marks on top of my factory roof rack from the wood at the top of my garage door opening.

I say go for it. It'll work!

If it doesn't you can always just put the old parts back in.

A good idea, but if you want to make sure you don't get any scratches/damage to roof, try putting the wood blocks on the top of the vehicle. If you stand a 2x4 on end, cut to the length of the amount of lift you want to try, if they hit they will only fall over with out doing any damage.

I like this as well, even easier! - I guess I am wondering how big to cut the wood block? Would it just be the 2 inches I get from the rear spacer and tires or is there some weird trig problem for factoring the height of the roof rack as affected by the lift to the front wheel...

It won't hit, not with the numbers you are giving. No part of the roof rack will go up more than amount of the lift. Directly over the rear wheels it will go up the amount of the rear lift. Directly over the frnt axle the vehicle will raise the amount of the front lift. In between the axles the roof rack will increase in height by an amount between the front and rear lfts, depending how close you are to one axle or the other.

I'd explain it better but I'm on a mobile device without a real keyboard.