Mash Motors Inc. Customer Reviews

I was getting frustrated with the lack of power in my 2006 H3 3.5L and was considering getting the H3 Alpha and taking a serious hit on the trade in. I did a little searching on the net and discovered Mash Motors Inc. can upgrade my H3 with a bigger motor than the 3.5L. After many long conversations with Mike, and I mean many, I finally decided to go with the conversion and send it out to him.

After getting my truck back and test-driving it, I couldn’t believe what a difference this upgrade made. It was everything Mike said it would be. I not only have a more powerful truck that is a dream to drive, but I also gained 52 extra miles per tank of gas after going through my first full tank of gas since I got it back. This is a huge difference from 3.5 to the 6.0L.

This guy takes pride in his work and really knows his stuff. He did a very clean and professional install and I would recommend him and this conversion to anyone who is considering taking their Hummer to the next level. Ride on!

Andy, CT

I purchased an H3 in June 2006 and was unhappy with the performance of the stock inline 5 cylinder. I did some research and found Mike Mash at Mash Motors Inc.. He converted my H3 to a 6.0 Liter Vortec, after which, I totally fell in love with my H3. I got more looks and stares in my vehicle. I smoked several mustangs and other vehicles (and macho males) off the line. They were pretty upset to be beat by a girl. I traveled many times out of state (on average 6-8 hour drives) in my H3 and enjoyed the ability to pass as I please.

I had been driving it as my daily driver until my son was born in Aug 2007. I then decided that I needed a bigger vehicle to handle the stuff needed for a baby. I was looking into several types of SUVs, and I was very interested in getting an H2. I purchased my H2 at the beginning of 2008 and soon realized that I was missing the power of my H3. I decided that another call to Mash Motors Inc. was necessary; my H2 needed a conversion done. I had Mike put a Duramax diesel into my H2, and I am in love all over again. My gas mileage has doubled over the stock engine. I am very impressed with the inside of my engine compartment – it looks stock. I have taken my H2 on a few road trips and love the added power.

Miranda – Happy Duramash H2 and 6.0L H3 Conversion Owner

I’ve owned almost ever kind of SUV: a Jeep Grand Cherokee, Jeep Wrangler, three Suburbans and three Hummers. I’ve sold all of them in less than a year. My first H2 was a standard black one; I loved the way it looked, but the performance sucked. After a 60-year-old man in a beat up old Chevy S10 beat me in a stoplight to stoplight race, I knew it had to go. My second H2 was Whipple Super Charged. It was pretty fast, but the engine kept having problems and the MPG was a dismal eight.

I started to fantasize about an H2 that could drive like a sports car and still get decent miles per gallon. I started doing some research into what it would cost to convert it to diesel. I found a wrecked pickup with 65K on the engine for $15K and found someone that would do the conversion for about 1$5k. While doing more research, I found Mash Motors Inc. Inc. on the Internet. For less money, Mash Motors Inc. would put a new engine in my Hummer!

I sent a black H2 down to Wichita, Kansas. Mike and I talked back and forth about all the different options, and they are limitless. After about three weeks, my Hummer was done. I flew down there and drove the H2 back to Minnesota. This is the first vehicle I’ve owned for longer than a year, and I still love it. It’ll accelerate faster than any SUV or pickup, and faster than most cars. I towed a trailer from Minnesota to California, through the mountains, and very seldom did the thing leave sixth gear. I get around 20 MPG. I’ve had a few user errors with my H2 and Mike has always been able to help me out.

I’ve had it to the shop for the regular maintenance and all the mechanics have told me this H2 is amazing and the conversion is just impressive. My only regret is that I didn’t do this a lot sooner. I wouldn’t have wasted my money on all my past crappy SUVs.


I wanted to thank you for your work on the 2008 Hummer H2 that you converted for me. To be honest, I was initially concerned about sending my H2 to you since the shop that originally started the conversion really messed things up, and after several months of trying to get my H2 to run, they eventually gave up. The reason they couldn’t finish the project is because the 2008 and newer H2s have a different wiring setup than the older H2s. Prior to sending my H2 to you, I called about a dozen shops nationwide to see if they have ever successfully converted a 2008 H2, and the responses were negative. That’s when I contacted you, and you were the only shop that had previously converted a 2008 H2. I immediately sent my H2 to you to correct the previous shop’s mistakes and finish the conversion, which essentially meant starting the conversion from square one.

What the previous shop couldn’t accomplish in several months time, you accomplished in a couple of weeks. The end result was the cleanest, most stock looking Duramax H2 conversion I have ever seen. After the extensive modification that you did to the H2, I picked it up from your shop and drove it to my home 1,500 miles away without any problems whatsoever. This event is truly remarkable, and clearly demonstrates the reliability of your work. Your constant attention to detail, extensive expertise, and obvious passion for the work that you do has allows you to create beautiful, powerful, and reliable custom vehicles for your clients, myself being one of them.

Looking forward to working with you again soon.


Mike, I wanted to write you a sincere appreciation letter on my behalf for doing an outstanding job on my Hummer H2. I checked around when I first had the problem with my airbags and you are the only guy who knew how to fix the problem and also adjust them for the lift kit that was added to my Hummer H2.

This was the starting point of a good business relationship. Next, you let me know about the supercharger, installed it and then eventually, I just had to have the diesel conversion. I was immensely satisfied with the results. I shopped around prior to doing the diesel conversion with you at another shop locally in Wichita, Kansas, that specializes in the same type of conversions. However, after several visits to each shop, I noticed that you seemed to get jobs finished.

Your personal customer service with me was the deciding factor in my choice to spend my money with your shop. I noticed the work that was done by both places and yours was far superior and more fine-tuned than the other. Not only are you a pioneer of the diesel conversion, but you are also very talented in suspension, transmission and accessory upgrades for Hummers. I would recommend your shop to any and everyone who would like a conversion for a Hummer H1, H2 or H3 due to the fact that there is nothing you can’t do, which was proven to me.

Most impressive was the turnaround time. My vehicle was actually completed and ready to drive within two weeks. Last, but not least, the follow-up on the business deal was awesome, checking up with me frequently and making sure I was satisfied as well as making sure that I understood all the pieces of the conversion and how it worked.

Wade – Converter Technologies of Wichita