How many of you have sold your car and had aftermarket rear gears installed, 3:73 or 4:10 to be precise?

I'm not planning on selling my car anytime soon but how do you adjust your speedo for the gears when you have the OEM tune?

 

I believe a dealer has to do it, but I'm not 100% sure.

 

Yes the dealer can do it, I had that done by dealer once on my Lightning and then got a tuner. But on a trade-in I see that as the dealers issue.

 

Rich, If you have your stock tune stored in an SCT tuner can't you update the stock tune for the 3.73's ? Just like your custom tune.

 

if you do that, then i think that the tuner will be locked to the car. i think he is trying to be able to keep the tuner for his next car or to be able to sell the tuner separately. could be wrong.

 

I'm just thinking ahead. If I sell the car someday and the new owner doesn't want any of the performance mods and wants to run it with the OEM 87 octane tune from Ford how do "I" adjust the car for the rear gears?

 

Here's what I did....... removed the blower, cams, etc. everything except for the headers and the rear end gears; returned the car to the stock tune (sold the tuner) and left a few business cards for a local tuner in the glovebox. After the car sold, the new owner contacted the local tuner and bought a new tuner and tune to correct the speedo, etc.

 

Why not just include the tuner with the car to help a brother out?

 

I just learned this week on another forum that the local Ford dealer can only adjust your speedo up to 3.73's. So in other words if you leave the gears in and take the tuner with you, then 3.73's can be adjusted for by the Ford dealer service dept. without your tuner, but 4.10's cannot be adjusted for because the calibration tool they use only goes up to 3.73's.

I had 4.10's before I got my tuner. I took it to Ford and they re-calibrated the speedo, but it was still off some.
It took the tuner to get it right. So if I go back to stock I'll be stuck with doing what Tom did, or leaving the tuner with the car, or removing the 4.10 gears I think.

 

on my ranger I adjusted tire size and axle ratio to correct my speedo. I have 4.10's and 32's on it.
I used the Ford IDS.

You need to mess with tire size to make the speedo as correct as it was stock.

 

Didn't know you could do that too.



I wish Mac Haik Ford would have known that in 2007.

 

Its up to the individual, I work at one and wasn't satisfied with the lack of options lol
I had to do the math, what tire size to trick it to for it to read correctly.

 

It only goes so far though.