[brandonjansen]

Hey guys,

So a few of you know or have seen that I put 35x12.5 Toyo MT's on my 2012 Ram 1500 4.7L. I do have the Bully Dog GT for Hemi Plus on my truck so I retuned it for the larger tires. The rough measurement I took of the tires was 34.5" so I first installed that in the tune. Driving home from work yesterday I pulled out my GPS to see how accurate my speedo was. Turned out it was still off by 8-9%. So last night I went on Toyo's website to find what their actual measurement is for the 35's. They said they are a true 35" so I decided to give that a shot (even though I didn't see a 1/2" changing it much at all). Well this morning driving to work nothing changed. It is still out 8-9%.

I'm wondering if any of you have had this issue or what tire size you've entered into your tuner with the 35" Toyo MT's to make your speedo correct. For some reason I have a feeling it might be a problem because I have the 4.7L and not the Hemi... I know there aren't a lot of guys running these tuners on their 4.7's yet, especially with 35" tires. But I'll take the input from the Hemi guys as well, anything helps.

I'm expecting I'll probably have to go to a Bully Dog tech with this question. Unfortunately I work during their support hours so it's hard for me to spend the time plugging in my tuner to the computer and going through it with them. That's why I thought I'd ask here first.

Again, any suggestions/input you have is appreciated.

Thanks, Brandon.

 

[gonefishin776]

I think when the tuners first came out people were having this issue of the tire size change not actually working.

Contact Bully dog, I think there is an update or something

 

[brandonjansen]

I think when the tuners first came out people were having this issue of the tire size change not actually working.

Contact Bully dog, I think there is an update or something

Ya that's kind of what I expected. I think I'll download all the Bully Dog software to my work computer and then tomorrow take all my stuff here so I can actually get it figured out.

 

[gonefishin776]

Word, sounds like a plan. Hopefully you get it straightened out. I'm pretty sure they fixed it, I haven't read anything about people still having issues.

 

[brandonjansen]

Okay, so for anyone wondering how to resolve this issue (RyanB, you will be one of them) here's the answer.

The software version from the update agent is 1.1.4.2 A00A. This is not the correct software for the Bully Dog to function correctly. I'm not sure if that is just for the 4.7's or if it includes the 5.7's as well. I believe I saw a post from Sledslvr (name might not be 100% correct) that he installed the new software version on his Bully Dog for his Power Wagon so I'd guess everyone could benefit from this update.

So the new software version is 3.1.4.2 A01A. After chatting with Bully Dog tech support on the phone they emailed me the new software with full instructions on how to install it. Took about 5 minutes. They assured me that this should solve my problem. I will install the tuner back on my truck this afternoon and see how it works now. I'll post another update later tonight or tomorrow with the results.