Do these transmissions still have the plastic speedometer gear in the tailshaft like the older 727s had? I was talking to my friend about my crappy fuel mileage and remembered that I have taller tires than stock on my truck and that may be throwing my readings off. Can you go to the dealership with a tire size and gear ratio and get the proper gear???

 

I think you can take all onfo to dealer, but I think that there are only A few choices as far as speedo gears. Try a company like DTT or ATS they probably have the gear you need. As far as the mileage, the winter blend fuel will knock off sometimes 3-4 mpg.

 

sorry for the error, that should read, take all INFO to dealer!

 

I am only getting 14-15 even in the late summer and early fall with no A/C running. I did get 17 mpg coming home from Alabama this weekend when I set the cruise between 70-75. That's the best I've gotten yet. Man, if I could only drive 65 mph I'd probably get 20 mpg!!!

 

The speedo pickup is located on the top of the rear axle housing it is the same sensor that runs the anti lock system. You can take it to the dealer and they can flash the computer for a very limited size of tires. Something new with the 24 valvers. Why cant they leave a good thing alone. lots of luck.

 

If I recall max dealer can adjust for is 265's. There are a couple of correction type boxes out there for this but I have not used personally. I am thinking Abbott or something like that is the name of one of them. You might try giving Rickson's a call (the guys who have the 19" wheels for our trucks I think I saw one on their website)

 

think of the difference as a bonus. really. Yes, the dealer can calibrate for 265/75-16 tires. Then consider that:<br><br>285/75 is only ~4% off<br>255/85 is only ~4% off<br>295/75 is only ~6% off<br><br>think of it this way: <br>you're mileage is always better than you calculate at first<br>you get to go further before the warranty runs out<br><br>the only downside of the larger tires is the mental correction you have to do for the spedo -- you're actully traveling faster than the spedo says you are. But thats only a few mph and easy to estimate. 4% of 70 is 2.8 mph, 6% of 60 is 3.6 mph, etc.