Bully Dog - 40420 - GT Platinum Diesel Diagnostic and Performance Tuner with 4-Preloaded Tunes

This should be a 3 star review but I feel bully dog tech support really deserved the extra two stars. I bought this through amazon prime and paid the extra bucks for the next day delivery. It showed up right on time and included everything that it should have. Amazon's job is done and they did perfect. The bully dog package did not include a complete instruction book it only included a quick start guide and a website to down load the instruction book. I followed the quick start guide updated the unit and installed it on my truck late afternoon on a friday. The unit malfunctioned leaving my truck doa. So I downloaded and read the instructions on one of the first pages it clearly states do not start the process until you verify that the tech support it open. By this time tech support was closed for the weekend and I was out my truck. First thing Tuesday I was able to reach tech support and about an hour later everything was fixed and working perfectly. The bully dog unit needed a coprocessor flash in order to match my duramax ecu. After this was completed the unit works perfectly. All of the on the fly tunes work excellent I love the improved fuel economy and the driving coach feature really helps me with my driving habits. It is cold where I am right now my normal fuel economy was around 13-14 mpg before it is now 16-18 and my last highway trip I managed an average of 22. Normally this would be around 18-19. I hope when it gets warmer it will improve a little more. I am happy with the bully dog tuner I only wish it included the instructions instead of a quick start guide. I am slightly frustrated with myself for not downloading and reading the instructions first.

Alright so first thing I'm tired of people talking about the mpg I want to hear the hp and let me tell you YESSS I love this thing power for days. Let me just say some pros and consPros it works l, it adds ton of power, small doesn't bug you when driving, lots of options for changing things, adds ALOT of gauges, and easy to see and readBullydog support was greatCons (IMO)install sucks only because it's slow to setup, I have an 2003 chevy duramax 6.6 lb7 so because of the age I had to contact bullydog and have them add some files to my chip through my computer to make it read my pcm, direction suck including their video on their website, just call them and walk through with them,I will say I love it I don't think it actually adds the amount of horse power it says but it definitely adds ALOT I would definitely have your transmission looked at before getting this if your going for power if your going to just get a little power for towing your fine but I have mine set on extreme and the tranny shift point kinda scare me because of how it feels it could just be me but idk I only rated 4 stars for 1 reason the amount of trouble I had to go through to install it but other then that so far I'm very happy and I mean very sorry for the long post hope it helps with your decision

First I did an online update but it would not install on my 12 RAM 3500. Called BD and they were great customer service but had to manually install the updates. We are RVers and pulling 17,500# 5th wheel. I have tried different settings, but I do not see that it helps at all. I keep it hooked up all the time so I can easily switch settings but I just do not see that this is making any difference. I purchased to get better fuel mileage but have not seen any significant difference, do not see an increase in power, I am not even sure it is working...although it says it is. I would return if possible...but I think I waited to long...been trying different settings to see if I can feel the difference...but I don't. Waste of my money!! Sorry guys but I cannot give it a good rating.

Tuner does not support a deleted truck. What’s the point?? Had to return.

Install went fine although it is completely lacking in documentation. Luckily there are some YouTubes you can reference, My first issue is that is takes FOREVER to come out of engine warm-up mode sometimes, that means I'm already where I need to be when it finally does. My biggest issues are that I'm not seeing any mileage gains, and that the manual DPF clean flat out doesnt work, just stays in "Waiting for DPF ready" mode. Called tech support several times, they had me flash the unit even though it had the latest update, now supposedly they escalated it to "Engineering" and I was told not to expect anything for at least a week. Goes without saying if they cant get this working its going back to Amazon. If they do, I'll revise the rating. Not sure if I'll try another brand after that since all the reviews had this one the best. Thinking about trying the SCT version but I'll see what happens. So far not worth the $450 I paid.Update: I returned it. After waiting weeks to hear back about a supposed fix to my issue I gave up. Trying the live wire + with some custom tunes from 5Star Tuning now so look for that review soon.

Bought it for my 2010 F350 and after days of trying to get to work it somehow damaged the motor. Not sure how bad yet but it was fighting the original programming fo fuel control during the regen cycle and kept turning down the fuel and power mode when the Pryor temp got to 1200 and to properly clean the DPF it needs 1600 so the constant back and forth fuel fight I think over heated the turbo and melted the seal causing it to burn all the oil out of the engine and smoke really bad while doing so. At night it did not show up that well and wound up waiting for a wrecker to get it home. update the high exhaust temp it caused burnt out the seals in the turbos and had to replace both of them.

Have had installed on my 2005 chev 2500 Duramax for a couple of weeks now and do notice a significant difference in power and fuel economy. Love the shift on the fly feature to change power levels and the driving coach works pretty well also. The quick start instructions were pretty cryptic so you need to go online and find the full manual before attempting to setup and install. I had some issues with the downloading to my truck as it kept failing but the online support via chat function was excellent and helped me determine the issue and was successful on the third try after they remotely connected to my computer and the devise. You need to make sure you follow the manual precisely. Would give it a 5 but took more time to get installed than I anticipated.

Download instructions are extremely poorly written, but once figured out works flawlessly. The unit itself performs very well and provides substantially more power and torque which improves towing and towing fuel mileage. Yes, the increase in power improves fuel mileage when empty by up to 10% if you drive it as the fuel saver indicates. I had to down rate the product as the windshield mount, that comes with this unit, pulled out of the back of the mounting plate on 3rd use. The unit should withstand regular user use for a substantial period of time at this price point , however, it does not. Thus the down rating. The unit itself works exceptionally well otherwise.

If I could give 0 stars I would. Dishonest company ! I bought a bully dog 40420 and choses my vehicle type to be sure it was compatible, and click buy. A few weeks later received it, I didn't install it right away since I was swapping the turbo on my duramax and it was a big job. A month later or so I was to install it. I install it and when it comes time to update the tune. It tells me that there is a vin mis-match. Confused I called bulldog directly. They tell me that I got ripped off and that it was installed on another vehicle and remove without uninstalling it, meaning if I do want to use it i need to pay 250 usd ! To be able to use it ! What a scam. I've been trying to reach these guys since the beginning and no answer back. I played premium price for something new that is old and a rip off ! Buy directly from bulldog and never from them here. So basically I got scammed 600$ for an obd2 sensor !

Nice to know transmission temperatures and things like that but doesn’t really give me much more power and it cost me more in fuel

Should have added this a long time ago, very happy with it.