I purchased a used 2014 Ram 3500 and needed to get it inspected for any outstanding issues. I have never owned a diesel before so I googled what coud go wrong with the 6.7 Cummins engine and brought the list in with the truck. Trenton went over every item in the list giving me a ballpark estimate of the possible future repairs. Left the truck for inspection and there were a number of items that needed to be repaired. Trenton gave me a wealth of information of what to look out for and how to drive the truck for maximun longevity. Mad Tech Diesel Workz is where I will be taking my truck for future service. read more

Shop Suks , guys have no experience. Trenton worked on my truck 3 times and now won't answer or call me back due to major issues they caused when it broke down the following day . Typical crappy bad customer service mechanic . They pick and choose there repairs and then when they can't fix it there a ghost . Would not recommend this mechanic at all . Always just say no if you can't handle the repair or are just extremely inexperienced, it saves a lot of time . Reporting to the BBB. read more

If you own a diesel truck Mad Tech is the only place you should take your truck thank you for getting me back on the road safely .

Had a good experience at Mad Tech the other day. My diesel truck kept running the battery down if I let it sit for too long so I found a diesel shop that was able to find the problem. I can't tell you if the price was fair or not but the problem was fixed. read more

Trenton and his crew are awesome! I'm working out this way on a temporary contract and my van, a Japanese import, (Madza Bongo) started acting up. I called around to several shops in the area and nobody wanted to look at it. Trenton told me to bring it in and he would give it a shot. They were able to figure out the issue and fix it quickly and at a great price. Trenton and his crew are transparent, knowledgeable and honest. Being a woman I really appreciate finding honest shops that don't try to take advantage of my limited knowledge. I will be coming back before my next contract to have them change my oil and get me ready for the road. Thank you Mad Tech! read more

I recently ran out of fuel and my Chevy Silverado would not start even after adding fuel to the tank. I thought that maybe I burned out my fuel pump. I was ready to have my truck towed to Mad Tech Diesel Workz. I called in to see if they had room to fit me in. The person on the phone walked me through how to prime the fuel system. I tried this, and just like her advised, the truck started right up. Here i was expecting the worse and it was a fairly easy fix. Saved me a lot of money. I'm sure most other businesses would have had me bring my truck in and then charge an arm and a leg. Thanks for saving me, Mad Texh Diesel Workz! read more

Trenton and his team are amazing. Came in for a service and they were able to fit me in. The new shop is very nice. Able get authentic Mexican food and a haircut in the same shopping center. read more

Mad Tech Diesel Workz - Auto Repair Near Me - Rancho Cucamonga, California

So I made a appointment to repair my truck. I showed up on time and no one was there. The shop is shared with another business. And he told me that they were not coming in on that day. My wife Skip work I had to reschedule my appointment for the day. And they didn't show up to work. I think that deserves no stars. read more

Trenton and his crew are awesome. Have had my Ram serviced here multiple times and they always find the problem get the parts fix and return in a timely manner. Couldn't ask for more honest and reliable service. Thanks mad tech! read more

Excellent service and work! I will definitely use Mad Tech for anything that I need done to my truck.

Trenton does amazing work ! I've been taking my diesels to him exclusively for the last few years and the workmanship never ceases to impress me. Great job guys!! read more

Had a turbo coolant leak in my 2011 f250. Trenton got me in on short notice and was completely fair with pricing and worked to get the truck back to me asap. Fair pricing, honest assessment, solid workmanship. 100% recommend mad tech. read more

Trenton and his guys are great always take care of me whenever something goes on with my truck. Really speedy service as well and are upfront about the cost no games with them. Thanks Trenton! read more

Helpful, informative, on time, quality work!!! I don't know what else to say other than they do what you pay them for and a re very good at what they do. read more

I'm so glad I found this place. After dealing with the eye gauging with the Ford dealerships. I finally found a EXPERT in diesel mechanic and other vehicles. I found this place word of mouth after talking to other truck enthusiasts, this is my second time coming to this shop and I've been just amazed on the wealth of knowledge Trenton (owner) and his staff has shown. In a nutshell Trenton takes the time weather it's on the phone or in person to explain the details and possible issues with your truck or vehicle without those ridiculous Ford Dealership prices. I'm so glad I found this place and finally have a mechanic that can take ownership of my vehicles. When I picked up my truck i was supposed my truck was detailed and cleaned from the inside. But that's what happens when you take your vehicles to a local small business expert that takes his time. Thank you for the great experience at your shop. read more

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So I have a 6.0. Just had for about 3 months and there was black smoke coming out of the exhaust. I looked on YouTube to help me out. I went a got some parts to try to fix it. But that did not work. I found this shop not to far from the house. Give them a call. I explain what was going on with my truck. The guys on the told me with I mite be to bring it in. But do not drive it have AAA bring it. He was telling me, that if a drove the truck more I mite brake more. Finding out that the cost of a diesel mechanic is very expensive. I took his advice. read more

Trenton and his crew absolutely 100% professionals. Probably the cleanest diesel shop I have ever been to. Great service, great communication and recommendations and value. I'm so glad I met them. read more

Trenton was a great help, knowledgeable and friendly. I will continue to use Mad Tech for all of my Diesel needs. read more

Trenton is amazing. Very knowledgeable and does great work and fast work I recommend him to anyone and everyone who need stuff done on their diesel read more

OK just moved to Montclair and needed a Diesel Mechanic to insect a possible truck I was going to buy. Above and beyond help full and informative on every inch of the drive drain for both trucks I took to them. After the purchase they hit me with a bill I wasn't ready for but BUT I must explain I drove out of there with a truck response I wasn't ready for either! ! ! There amazing and worth every penny. They actually turned me down twice on me asking for upgrades and said I didn't need to spend the money.....Who does that now a days. So my take away is Mad Tech is - Extremely Knowledgeable and Honest - Honesty when its hard to find now a days. When I said sorry for all the questions there answer was " That's what I'm here for, come back and ask more questions latter" Wont let anyone else touch this truck. read more

Trenton is the man! Excellent service and knew my vehicle very well! Would recommend and will continue to service my truck at his shop!

Trenton got us out of a tough spot today and we couldn't be happier. Knowledgeable and helpful in every way. We will definitely recommend to all our friends and family and will always be appreciative! Thank you Trenton! read more

If your reading this, you have found your new mechanic. They are the best. I can't say enough. read more

When it rains it pours! They tried stealing my Chevy 2500 back in January. They punched out the door lock and ripped the column apart and destroyed the ignition trying to start it. Luckily they didn't. I was still able to get it started with my key if messed with it and juggled it around. February rolls around and registration is due in about a month. All of a sudden my check engine light comes on. I take it to a shop in Downey, they scan it and tell me its my EGR valve and cooler. They quote me some ridiculous price. So I call my buddy Paul and tell him about it and he says there crazy. Take it to my "buddies shop Mad Tech" ask for Trenton. Went by there and after talking with Trenton for about 5 minutes I knew I was in the right place. He told me that he really doubts it's my EGR valve in cooler because they rarely if ever go out. So he scans it and he was right! I had a bad M.A.F. sensor and 2 bad glow plugs. He suggested that I do all 4 on that bank since it was already apart and glow plugs are cheap. When he was scanning it he also noticed my door lock broke and my Ignition all messed up and he said he could fix that for me also. While working on it he noticed my font end will need some work in the future. No pressure on doing it now. Just something you will need to address when yoy can. Trenton is straight up HONEST. My truck will go to no other place but to Trenton from now on. I cannot recommend this shop enough. read more

Do not take your truck there half ass mechanics it will cost you more money after they touch been to 3 different real diesel mechanics for problems after they touched my truck I would leave a no star if they would let me read more

From the moment my truck was towed to this shop I was contacted and kept in communication about what was happening with my 2006 F350 6.0 power stroke. Expert knowledge and excellent mechanic had my problems solved with different options for completing the bulletproof.... Honest and reasonable, future maintenance will be done by this business.... read more

For all you guys that have Diesel trucks, I highly recommend you see Trenton (Owner) he is a fantastic guy and service is excellent!!!

My Ford was having issues and I had a good deal of deferred maintenance as well. Took it to another mechanic who gave me a long list of expensive parts to replace. Got a second opinion from Trenton who looked at it and saved me over two grand by figuring out a bolt had cut through the manifold and not that my turbo charger was going like I was prior told. Great service, detailed explanations, well organized and clean shop, techs friendly and knowledgeable while being a true value, I was one happy driver when I got back my daily family hauler. One final note: When I dropped of my vehicle I knew I was in good hands when another customer came in from Bullhead City AZ just to get his truck repaired at Mad Tech. read more

Took my truck to Trenton and his Team and they were amazing! Professional and Courteous. They were honest and quick with their work. Shoutout to Andrew for the knowledge he game me about work I want on the truck and shoutout to Trenton for his professionalism! read more

Spoke with Trenton over the phone and explained what was going on with my truck he said that he did not service Range Rovers but to come on down and he would run a diagnostic at no charge so at least maybe I would know what I was dealing with. It's been a tuff year in a half for our family we've lost family members and employment so I truly appreciate his generosity & kindness and would recommend Mad Tech Diesel Works to anyone who's looking for a trustworthy business read more

Had my truck in to get some work done tore the whole motor apart had it put back together before my desert trip truck runs great! Haven't had any more problems! Would recommend to anyone that needs a great mechanic read more

Trenton is the best around for diesel repair. I had my oil pan changed and my turbo boot fixed and the work was was perfect.

Great customer service fair price. Highly recommended. They worked on my Ram 3500. I will be a return customer.

Found a great place for diesel truck service and repairs. Owner is extremely knowledgeable on all types of diesel engines, their functionality and maintenance needs. His staff have the same expertise and are helpful answering your questions. read more

Took my Dodge 2500 Diesel to Trenton from Mad Tech Diesel Workz on a Friday by tow. I told him I used my truck for my business and needed it back on the road ASAP. He said he could do the job and I trusted his reviews. I called him on Mon then Tues and he said he was still working on it both days and couldn't get it started. Went in on Wed and physically spoke to him and he still didn't have an answer. Said he was sorry and that it was a challenge for him to get it started however he did change the battery terminals because they were bad. He said he was going to try a few more things to get it started and get back to me. Thurs he calls me and says he got it started. Took my truck home and got up Friday morning to start it and it won't start and Trenton won't answer his phone. Finally he answers late morning says he's out with his family and if I want to bring the truck back he is going to charge me $200 per hour for diagnostic. This guy had my truck 5 days and couldn't fix it and wasn't professional enough to tell me he couldn't do it from the start. Why would I take my truck back to a guy that can't fix the problem. So now I'm out $584 for battery terminals, a fuel filter and loss of a week's worth of work. In the end my truck still won't start. Never again, I'll never go back to this place! Horrible!! read more

This is hands down the best diesel mechanic around in the inland empire. Trenton is a true example of how a shop should be run, very professional, honest, organized and a man of his word. I wouldn't take my truck to anyone else. Has kept my 2003 6.6 duramax running great! Thanks Trenton!!! read more

My truck threw a "Check Cages" light and I watched the battery/alternator needle fall. I was traveling through so called my husband and he hopped on the web to find me a place to limp the dying truck to. He found Mad Tech Diesel Workz. They were ready for me as soon as I pulled in. The problem was diagnosed within minutes and parts were on the way. I think I only spent a few hours there and it was done. When I came in I was making arrangements to stay the night and let my friends know I wasn't going to be making it. With the help from Trenton and the team, I was able to see my friends after all and stay on time for my trip. I'm beyond thrilled with the service. If only I lived in the area, this would be the only place I'd bring my diesel for service. read more

Just wanted to take some time to give these guys a review.. I'm not one to leave them very often but I must say I was thoroughly impressed with the service I received. If you own a diesel you know that great service is hard to find. These guys made it as painless as could be. My first interaction with these guys I called, no answer.. but to my surprise I got a call back from them stating they had a missed call.. no big deal right? But that fact that a business owner would take the time to respond and prospect a business opportunity goes a long way in today's society. Secondly I arrived at the shop and was blown away by how clean and orderly it was.. prior experience with mechanic shops leaves me with nightmares of magazines and miscellaneous stuff stacked on top of a desk and floor. Over all it is very apparent these guys take great pride in their work.. they've earned my business going forward, and I've already starting spreading the word among family and friends, I would recommend these guys to anyone. Thank you for your great service! '14 RAM 2500 6.7L (turbo control mod.) read more

Just got our truck worked on and the turn around time was so fast. We have done so many trips and the truck has never ran better. Would definitely recommend going to Mad Tech Diesel! read more

Trenton and his staff did a great job on my F250 diesel. His shop is extremely clean and service was way above the rest. He took the time to explain the service and also uses great quality parts. He kept the old parts without me asking. Will definitely go back for future services. read more