when you do a body lift, and put 33's on with a smaller wheel, do you need to recalibrate your speedo?

 

naw, it should be to much off. maybe 5mph off at 70 mph.

you can tho if you want, but i dont think its worth it

 

it will be off any time you change the tire size from stock

 

What is the biggest tires you can clear with a body lift

 

i would recalibrate it. dont want to get pulled over for going faster than you thought you were. and constantly wondering how fast your really going.

SCT Tunner or Chip from Doug will recalibrate your speedo

www.bamachips.com



they say just 33s. but whatever you can fit, ive seen 35s but its tight.

 

I have 33x12.5x15 with a 3inch body lift, and my speedo is 5mph slower than what im going, just find one of those cop stands sometime and check yourself....or else have a friend drive beside you and tell you how fast your going....

 

that doesnt make sence man you should be going faster.. with the bigger tires the axle has to spin faster to turn them so the speedo would be higher then you were.... i dont think that your correct on that one man...

you can get it recalibrated but depending on how much your go up in tire size i wouldnt really worry about it.. i went up in tire sizes 9 inches bigger then stock.. and lol it was cool my speedo was supposibly off alrmose 20 mph. lol...

 

kurt dont you miss being up high?

and i think your wrong the bigger the tire the slower the axle turns.

 

nope im pretty sure im right on this one.. but if you dont believe me take a 33 and a stock tire put a line of tape about 4 foot away.. see how many times you have to roll the tires to the tape which one gets there first? hehehe i win

yeah i miss it but low and speedy is cool too..

and now that i think about it we were both wrong it turns at the same speed but the bigger tires make it faster, going back to the stock against the 33 say it takes the stock 3 turns to go that far and takes the 33 2 turns so it would be the same speed for the axle but faster because of the tires.

 

ic i think i would miss being as big as you were, your truck was sweet.(it still is dont get me wrong)

and if it turns faster why do we regear when we get bigger tires? and why does the rpms run slower with bigger tires?

maybe we are both talking about different things. but i know the axle will turn slower with bigger tires.

 

we regear so the engine doesnt have to work so hard, i really think your incorrect with the axle thing, but we shall see when someone who really knows there stuff jumps in.. maybe bob or someone..


but yeah i miss being that high up it was nice but the truck ran like crap tho so there are the trade offs but it was cheap to go back and i learned allot of stuff during the process, just an expensive mistake buying that lift..

 

The axle will rotate the same speed, but the tire will rotate a bit faster(in some wierd sense) but in one rotation of your axle, your 33 inch tire will have gone a lil further than stock 28.9 inch tires.

So pretty much, if you get bigger tires, when you think you're going 55 you'll really be going sixty. You go a few mph faster than what your speedo reads. And I know, because my winter tires are bigger, so I have to watch out for cops since I forget and go 60 in 55.

Aaron

 

yes!!!!!!!!! i win! hehe i knew i was right lol..

 

i think we are talking about different things. and arron you answered the question by saying --

that right there tells us the axle spins slower with bigger tires.

 

anyway, just a note, there is a chance if you change the tires without recalibrating your ECM will take a $hit. it happened on mine, the tranny went into limp mode when i went to 32s. I HAD to get a programmer to fix it. its not a common case but it did happen to mine, so its something to keep in mind. that and your speedo will be incorrect, your ECM will be using the wrong math to make its calculations, and your ABS may not function properly

 

but thats what i said and he said that the axle spins at the same speed, and it does the larger circumfrance of the tire makes the truck go faster and have the speedo think because the axle is spinning at the same speed as before the tires were added the speedo would be LOWER then what you are going, no matter what the axle is always going to be the same speed as before the tires were added...

 

you guys are all arguing over differnet things.

EITHER!!

The axle turns the SAME speed and the tires go FASTER
OR
The tires go the SAME speed and the axle turns SLOWER

THOSE ARE THE SAME THING. ENOUGH NONSENSE, I HAVE A HEADACHE!!

 

thus why i dont buy auto's


and yes with a bigger tire your speedo will be at a slower speed then before its if you get smaller tires the speedo goes faster at the same speed. still dont beleave come on over i'll so ya

 

**** it...

Mine is off..

 

ok, what about when you go down to 15x8's, anyone ever had a problem with the wheels hitting the calipers/rotors? or better yet, is there a way you can find out without going to the shopand actually trying to put the wheel on....which seems to be the easiest surefire way.

 

15x8 wheels with 3.25 to 3.75 backspacing will work good.

 

do these auto trannies use the ECU to help determine shift points? on the F-Bomb it does. u can recalibrate the speedo manually (2 minute process). enter in the tire spec after doing some basic calculation and the speedo will be set to the tire size. wam bam the speedo is fixed and the tranny will shift for the right tire size. mine was set for 235/75/15 (28.--) and i was running 33s so it made a HUGE difference.

 

kiel how do you change it manually? id never heard of that and id like to know how.

shawn, if you have an 03+ 4wd you will need 16 inch wheels or larger

 

its an 01.....it has 16's from the factory. i know you can put 15's on it, ive seen it done. i just dont wanna be causing a problem i have to deal with down the road. btw, could a tire shop or something recalibrate my speedo for me?

 

This is the first I have heard of this one???? I thought many people on here have gotten 15's along with there 33's.....