Devil Mountain Diesel - (925) 954-8582 HOURS Devil Mountain Diesel - (925) 954-8582 MAP Devil Mountain Diesel - (925) 954-8582

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Devil Mountain Diesel - (925) 954-8582 HOURS Devil Mountain Diesel - (925) 954-8582 MAP Devil Mountain Diesel - (925) 954-8582
Call Today! (925) 954-8582 Labor Rate Increase 3/1/2021

Customer Reviews for Devil Mountain Diesel

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Here’s what some of our Walnut Creek, CA customers are saying about us:

We had both our trucks die on us. One needed a new turbo and the other is getting the full 6.0 bullet proof treatment. Very impressed with the communication, organization, and expertise of everyone at Devil Mountain Diesel. Pricing is very fair for the experience and expertise of the mechanics. Officially swapped shops and will be coming here all the time.

Wolfgang Croskey Devil Mountain Diesel Customer Review

My first experience at Devil Mountain Diesel was a positive experience. Kim in the front office was very helpful. She was knowledgeable and was able to answer my questions. She was able to reschedule my appointment due to my work schedule. Mark is one of the owners and he was glad to answer my concerns regarding my 2017 Ram 6.7L Cummins Diesel truck. They changed all the fluids, all filters and replaced the OEM transmission pan, front & rear differential cover with aftermarket ones. I'm having DMD do all the future maintenance and upgrades and not the dealership. I highly recommend DMD for all your Diesel truck repairs.

Vicente Zambrana Google Review

Some people hold a higher bar for quality than others. These are those people.

Casey Morris Google Review

A very proud customer to have done business with you all. The confidence to fire up after being stranded with my trailer on my birthday is like no other. Now they did have to calm my nerves a couple of times but it was all because of some unforeseen issues and an oil pump that did not want to cooperate. After a full on heavy duty bullletproofing and some cooling solutions no one else will touch that truck unless I'm washing it. Just trust the process and wait for Kim to call. Excellent workmanship with a stock appearance. Highly recommend DMD. Thanks again fellas!!

Jalil Whitfield Devil Mountain Diesel Customer Review

I have to give a great review for mark and his staff. So, my Ford F-250 needed repairs It was head gaskets and the usual 6.0 items. And so they bullet proofed it and it runs great. The price quoted was fair and the repairs were done right and in a timely manner. They took care of my wife and l. I definitely recommend them as a shop you can trust.

John Van Etten Devil Mountain Diesel Customer Review

O Helped out with my truck. Sold me some great parts and plenty of good advice. Would highly recommended

Dennis Larson Google Review

5 Stars!

Cole Hutcheson Google Review

I will never be able to express my gratitude to this company and the team it holds. I bought a lemon of a truck, 2003 F250 with a 6.0L motor. I took it to a mechanic shop in Livermore where they only made my matters worse, originally I just needed the motor studded. I came out of that shop with more problems than I could afford. I contact this shop for a second opinion. Mark understood my concerns and was completely honest with me through my tragic ordeal. He showed me everything that I couldn't had seen buying this truck. I got ripped off by the people I bought it from and the previous mechanic. The story may have been different if I'd taken it to Mark in the first place but never the less. He was straight up and honest with me. I bought a new truck already studded and he took the time to look at my new truck. I understand a lot more now that I have dealt with Mark and Devil Mountain Diesel. I will never take my diesel anywhere else, even if I moved. It's worth the drive. I can not tell you how satisfied I am with Devil Mountain Diesel and their quality of service. I want to give them 5 stars and a million if I could. They changed the direction of my life because my truck is my lively hood as a welder and single mom. It can be very stressful being a women driving such huge truck and not knowing too much. Mark changed that for me and his company. Thank you guys so much I can not thank you all enough. Especially Mark, you just don't meet people like him. I'm very blessed to have crossed this kind mans path. Thank you so much. I plan on taking my new truck there for its lift. Thanks again

L R. Yelp Review

I highly recommend Devil Mountain Diesel. My truck need repair Mark was able to take it in the morning I called. He diagnosed the problem later that morning, got the part in the next day and had me on the road in time to depart on my vacation! He also dealt with The warranty company. Which is something I hate having to do. Both Mark and Jason are very personable And professional. Need your truck worked on or just maintained? These are the guys to see.

Gary L. Yelp Review

Took my 05 F350 in for a complete "bulletproof" job. The work was done immaculately and on time, and the customer service was very good. I have been driving the truck now for several months since the work was done and it runs flawlessly. Thank you !

Efrem S. Yelp Review

Devil Mountain Diesel takes good care of my F350. Courteous and helpful.

Robert Stoffregen Google Review

This is the place you want working on your Ford Diesel . Bullet Proof in Arizona recomended them for the job so I didnt have to ship my truck. This crew put a Full Bullet Proof kit in My 2006 Ford F-250 and its Running Great.
Very knowledgeable folks very Honest,Great work.

Tyrone Daigle Google Review

5 Stars!

james riley Google Review

Take good care of customers. Very concencious do only what is necessary
Very popular plan ahead for schedule date

Daniel Richards Google Review

5 Stars!

Jim Weston Google Review

We have had a ton of mods and maintenance done on our fleet of off-road racing support vehicles at Devil Mountain Diesel. Nice guys, very knowledgeable, and cost effective. I highly recommend them and will continue to take my vehicles to them exclusively. When it comes to our trucks we want it done once, done right, and built to withstand a beating.... These guys deliver that!

Dalton Miesen Google Review

We have been taking our 05 Excursion to Jason and Mark for several years now. We actually don't trust anyone else to service our vehicle and drive to them for simple oil changes from Tracy. We are very confident in their work and will remain a loyal customer.

Lindsay O. Yelp Review

Jason worked on two of my diesels years ago when he worked as a diesel technician at Ford. It was always done right the first time and I never had any problems with his work. I don't own a diesel at the moment but when I get my next one I will be taking it to him for service.

Benjamin J. Yelp Review

Made a call to Devil Mountain Diesel a few weeks ago to see about getting the front pinion seal replaced and aftermarket exhaust put on my 06 Dodge 2500. After a bad experience at a different Bay Area shop (and there is not many diesel shops around) Devil Mountain was my final hope and I wish I had just gone there first. Absolutely worth the drive from Fremont to Walnut Creek for me. No more gear fluid on my driveway and my truck sounds great! I've already referred a couple guys there. Thanks guys, I'll be back.

Jack B. Yelp Review

Mark and Jason have worked on my Ford E350 Sportsmobile van conversion for years now. They gave it the 6.0 liter Bulletproof treatment as well as lots of other improvements and misc. maintenance work. They always do an outstanding job. In fact, I live in Utah now and still make time when in the Bay Area to drop the van off at Devil Mountain for routine maintenance. I couldn't be happier with their level of professionalism and quality.

Peter W. Yelp Review

Their hats keep the sun off my face in the summer and frost off my head in the winter. Get a hat, you won't regret it!

LT W. Yelp Review

My husband & I were visiting family and friends in the area when our F-250 diesel truck failed to start in my sister's driveway. After my husband tried a few fix-it ideas and troubleshooting to no avail, he called Devil Mountain Diesel to see if they had time to take a look at it on short notice, as we were scheduled to head back home to Idaho in less than a week!

They said they'd be able to fit in a diagnostic that day or next and let us know what it would take to get us back on the road. Had the truck towed on over and the guys were able to pinpoint the problem (FICM failure) and have it road-ready in time for us to leave for Idaho as planned.

Mark & Jason were friendly and professional, extending us the courtesy to squeeze in working on our truck so we could get back home. Although, unfortunately, the FICM they installed failed on us 50 miles from home, they stepped up and stood by their warranty.

After our local Ford dealer replaced the failed FICM, and we mailed back the defective part, Mark ensured that a replacement core was mailed back to us so we could receive the core credit here. In addition, a full refund of the part and labor was mailed as well.

My husband & I were impressed with Mark's follow-through, especially after my husband made an inquiry as to how long it would take for us to receive the replacement core and refund check. My husband had Devil Mountain also replace the serpentine water pump drive belt, which has been just fine.

We realize the FICM failure was not Devil Mountain's fault yet they stepped up and honored the warranty on the part and labor even though we were from out-of-state and unable to bring our truck back to them to do the warranty work. If you want a shop you can trust to stand by their work, these guys are true to their word!

Carolyn T. Yelp Review

Very impressive crew and shop. You will not be disappointed with the knowledge, cleanliness and the friendly staff.

Bill W. Yelp Review

These guys are really friendly and seem very knowledgable especially about fords I would much rather go here then the ford dealer. With that being said they charged me 120$ for what appeared to be a safety inspection. I would love to bring my truck back here but I will definitely think twice unless I have plenty of money to spend. I don't expect anyone to work for free but 120$ to tell me I need new brake pads, tie rods, and hubs is a little steep. I know places usually charge 30$ for similar inspections and some even do it for free like big o and les shwab in order to earn some business. I dropped it off because I was concerned with my engine and fuel system but didn't get any feed back on that but was still 120$ out of pocket.

Michael U. Yelp Review

These guys are awesome. I just bought a diesel my first and they took the time to show me everything I needed to know they set me up on a maintenance schedule and recommended things to up grade or repair but didn't try to out sale my needs.

Troy C. Yelp Review

After four visits to ford, plus another place, I brought my F-350 here for death wobble. Drives like a new truck! Up to Tahoe and back with no slop in the steering, let alone the scares. Thank you DMD.

David Eisenlohr Devil Mountain Diesel Customer Review

I'd like to thank Mark & Jason for the repairs they did on my truck when I broke down in the Bay Area while visiting friends and family. I was very satisfied with the work done. However, to no fault of their own, a part they replaced, which was an electrical component, unfortunately failed on my trip back home. When the service shop where I live diagnosed the problem I contacted them about the part failing. They said for me to go ahead and have the part replaced and send them the defective one back to check out and they would issue me a refund, along with returning a core to cover my core charge. They stuck to their word and sent me a full refund for the part and labor.

Dennis Thibault Devil Mountain Diesel Customer Review

Mark and Jason (the owners) have been working on all my vehicles for years. They are honest, ethical and get the job done right! I drive a high milage SUV, and it gets a lot of abuse...they keep it running great! Whether it's a tune up, oil change, or major service, they are experts at what they do. No run around...they find the problem and fix it quickly. I've had some nightmares at other shops. These guys are the best!

Brandon H. Yelp Review

Jason and Mark have been looking after my van since I bought it a few years ago. They've always been easy to work with and do great work. Huge thanks to you guys and your crew for getting the van-zilla done so quickly this week so I could make it to the races!

Michael Mannion Facebook Review

Brought my 6.0 in for Bullet Proofing and some fun mods too... absolutely awesome dealing with Mark and Jason, they're top notch guys and I can't wait to get my truck back. Great, clear, honest up front kinda shop. Looking forward to the results.

Brian Cook Facebook Review

BulletProofed, ARP studed, Fire ringed and new water pump 26k miles ago. Truck has run flawless since!!!!

BJ Whitman Facebook Review

5 Stars!

Monica Daigle-Kleisath Facebook Review

Saved our butt a number of times. Great mechanics!

Randy Davis Facebook Review

5 Stars!

Jeremy Claunch Facebook Review

5 Stars!

Roger Kevin McBride Facebook Review

Great work! I'm willing to drive an hour each way to have these guys work on our trucks!

Max Sheehan Facebook Review

5 Stars!

Mike Morang Facebook Review

5 Stars!

Joseph Cancilla Facebook Review

5 Stars!

Lindsay Bankert Ortiz Facebook Review

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