need some advice

Hows it going guys, I have a 97 blazer, 4 door 4x4. I did a 2" BL and slight t-bar crank w/ shackles w/ 31x10.50's. Lately ive been doing alot of high way driving and noticed that im stopping at gas station a little more than i thought. Ive been getting 18-17 MPG highway depening on traffic or how heavy my foot feels at times, but i usualy curise at about 70 most of the time. in town im lucky if i can keep it above 16 MPG. Now i already have all the basic performance bolt on's. I love how my blazer sits and looks, but i was thinking about lowering it. Take the lift and shackles off and may be toss on 18"s w/ with a good side wall. Ive seen 255/55 look rather well. Id like to keep some what of a different or unique look to my blazer.

My question is if i would take off the lift and tires, and put on a set of 18's would my MPG get any better? take in note that there is a fresh jasper motor and rebuilt tranny.

Thanks alot guys

You need to reset your speedometer to match your tires before you can check gas mileage.

I have the Hypertech programer installed, I set the computer to 31" tires as wells has improved shift points and firmness. I have also had a person drive behind me to double check and the speedometer does read correctly

Any adjustment to the torsion bars, (or adding or removing shackles to the rear) will affect camber and toe in. When camber is out of spec you can expect excessive tire wear. When toe in is out of spec you can also expect excessive tire wear and a decrease in fuel mileage caused by the increase in rolling resistance. If ride height is not within spec, it puts more stress on CV joints, suspension parts and steering linkage, as a result they will wear faster also.

When i went to play w/ the T-bars, i got new keys and shackles. When i put the indexed keys, the suspension had 0 give. so i took the indexed keys off and the stockers back on. When i put them on i tried to get them as close to factory as possible b/c i knew about the bad sides of T-bars cranking. After playing w/ the front end i got it aligened any way. They said the toe was in a little and the t-bars didn't seem like they were too high up or down. Im sure im pushing the front end a bit w/ bigger tires on the IFS and i wouldnt doubt that it is a slight cause of poor gas milage. I keep on top of any type of noise and keep everything well lube and maintained down there.

My bigger problem, life problem is i get bored after a while. I had this lift and tires on for going on a year and im getting board with it. So i was thinking about like i said above putting 18's on and if i can gain some larger MPG gains it will give me the extra kick in the butt to put my blazer and stock ride height with the hope to gain an aggresive look(im sorry a bone stock blazer just looks sad to me), but if i wouldnt gain that much (1-2 MPG) its not really worth taking everything off.

"They said the toe was in a little and the t-bars didn't seem like they were too high up or down."

There is an exact measurment and procedure for checking/adjusting the ride height. From their answer, it sounds to me like they don't know how to check it. If you'd like the procedure and specs PM me, they're quite lengthy.

when i got it done i told them what i have done do it. After they were able to get everything in to spec, they told me the toe was in alot, but they were able to get it in spec. I asked them if the t-bars crank made an differnce w/ the alignment and they said no, what ever i did, didn't effect it. It was a chevy dealership that i had it done at. I appriacted you willingness to help Old_master but its not that big of a deal. Im sure my set up would be hard to calculate ride height. And they probly didnt know what they were doing w/ when i droped it off, im sure they just read the work order do it and be done. It wouldnt suprise me at all if they just got it in and out, even though i asked them to make sure everything was fine. but oh well it still runs so im not gonna complain, yet

...I asked them if the t-bars crank made an differnce w/ the alignment and they said no, ... It was a chevy dealership that i had it done at. ... Im sure my set up would be hard to calculate ride height.


Wow, better stay away from that dealership, ...far away. They obviously don't have a clue.

Tire size has absolutely nothing to do with chassis ride height. The vehicle must be on a perfectly level surface, front to back and side to side. Chassis ride height measurements are taken from two places on GM T bodies: One is from the lowest inboard point of the steering knuckle, (close to the lower ball joint) to the ground. The other is from the center of the forward lower control arm pivot bolt to the ground. Subtract the knuckle measurement from the control arm bolt measurement and you have just calculated chassis ride height.

When chassis ride height is adjusted, the chassis is raised or lowered. The center link is attached to the pitman arm and the idler arm, both of which are attached to the chassis. The outer tie rod ends are attached to the knuckles, which do not move when ride height is adjusted. When chassis ride height increases, the angle of the tie rods increase and causes toe to increase. When chassis ride height is lowered, toe will decrease.

Even the slightest change in ride height will affect toe. Toe affects tire wear more than any other alignment angle. Chassis ride height MUST be checked and adjusted if necessary, before the wheel alignment. Chassis ride height affects wheel alignment. Wheel alignment does not affect chassis ride height.

...My question is if i would take off the lift and tires, and put on a set of 18's would my MPG get any better? take in note that there is a fresh jasper motor and rebuilt tranny.

Thanks alot guys

Sorry, rabbit trailed on this one and never answered your original question.

A body lift will only slightly affect fuel mileage adversely due to the increase in drag coefficient, (there is less ground effect and you're pushing more air than necessary). Larger "foot print" tires will increase rolling resistance, which will adversely affect fuel mileage. BTW, a body lift, if done correctly, will not affect chassis ride height or wheel alignment. My suggestion, for the best fuel mileage possible, would be to use the factory recommended tire size, calibrate your speedometer, have chassis ride height checked and adjusted, and then align the front end, (not at that dealership) ;)