schu

Anyone know if it is possible to make the factory computer work with the 315/70R17 tires and 3.73 gears or are we forced to buy a overpriced truspeed unit.

Thanks,
schu

phox_mulder

First off, what year vehicle?

Best thing to do is fill in your signature line (accessible through the Profile button above) with your model year, and any modifications done, as in mine below this post.

Probably not.
Consensus is that 265's are the biggest the dealer can program in.

Since you said 3.73 gears, I'm guessing you have a 2003, in that case you'd have to go with an aftermarket correction device.
Superlift Truespeed is the choice of most, including myself.
Abbot ERA is another option, but I have no info on that unit.

Last I heard, Superlift doesn't support the 2003's, but someone on this board made one work.


phox

LE

The SuperChips diesel tuner can handle your dilemma, as well as give you some extra power. I am pretty sure one is available for the 03 trucks. Mine was $300 (2002 model). LE

schu

Thanks for the replies, I added my truck to my profile as suggested above.

Next question:

How will a truspeed unit (or the tires for that matter) affect my warrenty?

LE

I don't think you would be able to call DC roadside assistance for a flat tire. Other than that I don't think it will effect warranty at all. I guess it would depend on your dealer. LE

gadgets

I'm looking for a speed calibrator too...the tires are sitting in the garage now.

SuperChips does not have a microtuner for the 2003 yet.

SuperLift says 'sometime next year, maybe...'

I may just put the tires on soon, before beach season is over!

If anybody knows a manufacturer that does have one, let me know, too!

Rene

LE

Not having the speedo calibrated just means the mielage will be a little slow. As long as you know where it is, it shouldn't be that big of a deal. SC should have a unit out before too long. LE

phox_mulder

I swear someone on here got the Superlift to work on an '03.

I know my CRS hasn't progressed that far.

Hopefully he/she is still around and reads this thread.


phox

Mark Thomas

my gps tells me that at 70 (on speedo) i am actually doin about 74 on gps

LinearX

Here is the link to the Superlift speedo correction box install.

https://www.dieseltruckresource.com/...threadid=14099

phox_mulder

That might be something worth putting in the Tech Facts, since Superlift is taking their sweet time getting it for the 2003's.



phox

WTTD

Isspro may be the answer. I was looking in my Isspro catalog today. There is an Electronic Ratio Adapter avaliable. Quote "This device helps obtain speedometer accuracy affected by tire size and rear end ratio changes. Instructions help you calculate percentage of increase or decrease necessary to correct the speedometer accuracy. Dip switches are then set to adjust the signal and calibrate the speedometer. Wiring is 12vdc ng keyed on/off, ground, input signal from magnetic sensor or signal generator and output signal to the speedometer." If anyone is interested just send me an e-mail, or pm. These are real reasonably priced.

schu

http://www.issproinc.com/Home/websto...peed_sd_3.html

Well $163 isn't that much cheaper than the truspeed so I figure I'll just buy one of those so that I can switch between winter/summer tires.

WTTD

How about $105 + shipping? If you write down the dip switch positions you could change tire sizes pretty easy.

schu

That sounds FAR more reasonable... is that what they had in the catalog? Also anyone test this on an 03 yet?