Gears & Axles - 3:73s and no tune Ok?

Hello yall. I am thinking about switching to 3:73 gears. I dont have a tuning device. Will it be ok to 3:73 gears without a tune? Ive been told the speedo will be off. How off will it be? I currently have 3:23 gearing. What else needs to be tuned? If i run this mod without a tune will there be any gains? What is the ups and downs of this mod? Any information will be greatly appreciated. Thank you for your time.

i have 3:73 and all i did was recalibrate my speedo. I dont think you normallly get codes from changing gears.

Tom

i just had my speedo calibrated today.itll be off about 4-6 MPH.


if you have a stock tune you can buy various programmers to adjust your speedo with.

if not just take it to a shop and theyll do it for about $50- $75.


nothing will be affected otherwise.gas mileage will go down considerably.at least mine did.


if you can get traction 1-2 tenths you should see in the 1/4.

I changed from 3.23 to 3.73 speed was about 8-10 mph off, but under hard acceleration the shift from 2nd to 3rd was sloppy as hell. It’s because the computer uses both the RPM & MPH to judge when to shift. I finally had the computer changed and it shifts fine now.

You dont NEED to tune anything but to get the most out of them and for your speedo to be accurate youll need to change your shift points and gear ratios.

I've changed mine with no tune.Speedo is off 6 mph. it shows aprox
6 mph faster than what you are actually running.Can I pick up
some tenths with a hypertech tune? I heard that basically it just
corrected the speedo and gains were negligible.
John