Driven by diesel

Jan. 8, 2021
Diesel power has always been the driving force behind any industry on the move, so when you specialize in repairing fleet and service vehicles like Tomlin Diesel does, most work orders at this Franklin, Tenn. shop are for middle- and heavy-duty trucks.

Diesel power has always been the driving force behind any industry on the move, so when you specialize in maintaining and repairing fleet and service vehicles like Tomlin Diesel does, most work orders at this Franklin, Tenn. shop are for middle- and heavy-duty trucks. 

“We can work on all the big rigs,” reports Jason Tomlin, the company’s general manager, “Freightliner, Mack, Kenworth, Volvo, but we do not see some of those trucks as much as we do the medium-duty trucks: International, Isuzu, even some of the bigger Ford F-650-750 trucks.” 

But with Ford, Chrysler and GM having upped their game in the diesel marketit’s the everyday personal pickups they’ve increasingly been seeing in their bays. 

“As (the U.S. automakers have) improved technology in some of these smaller engines, we see more companies and individuals buying what we call light-duty pickups because their overall horsepower and torque ratings are similar to what a mid-size diesel was capable of [a decade ago],” said Tomlin. We can actually fit more in our shop, so we enjoy those types of trucks. Sometimes they can be aggravating, just as any other kind of repair can be, but they have proven to be very fruitful for business.” 

Tomlin Diesel also works on a variety of RVs, school buses and delivery vans like the Sprinter. “Freightliner, Dodge, Mercedes — whatever emblem happens to be on the hood,” proclaimed Tomlin. “We work on a variety of equipment, such as generator units, Kubota skid steers, Bobcat, John Deere —anything where we might be a better option to make a quick repair than taking it in to the dealership.”  

It was under similar auspices that Tomlin’s father Mike founded the company back in 1986. “He started off doing a lot of heavy equipment repair, lot of A/C repair out of the back of his truck,” said Tomlin. “Over the years the business evolved into what we could get through the door. 

“Back then it was called Mike Tomlin Diesel,” he recalledIt was a mobile service based out of our house until he added some bays onto a pole barn, and we were there about 7-8 years. Then we purchased a building and started really opening up a lot of engine builds, etc., that we were doing for other companies.”  

But the shop grew a bit beyond what the elder Tomlin was comfortable managing, and with his talent focused on being a technician, decided to shut it down around 1996 to work for somebody else. However, with son Jason set to play a bigger role in whatever endeavor his father was undertaking, Mike decided to take another crack at independence and restarted the company as Tomlin Diesel.   

This decision may have been fueled in part by the tremendous economic growth the city of Franklin was experiencing. With many manufacturing plants being built in the area, this Nashville suburb had also become the American headquarters for corporations like Nissan and Mitsubishi.  

“Growth and expansion are all around us, so it helps being in the center of it,” Tomlin explained. “Definitely with us being one of the only diesel repair truck shops in town helps with just bringing in business to our location. We’re not so much service-call based as we once were; the majority of the vehicles we repair come into our shop, being that we’re kind of in the middle of town now. It’s a pretty good location to capture that traffic. 

“And the size of the building definitely allows us to take on those larger trucks,” Tomlin pointed out. “We can lift a dump truck bed completely in the air without hitting the ceilingSo we’re able to remove cylinders, swap motorstransmissions and differentials, and make hydraulic repairs.  

For in this market, hydraulic equipment is almost as important as the vehicles themselves. “We’ve got a crimper machine with which we can fabricate and make up hydraulic hoses,” he explains. “We’ve got flow meters to test hydraulic pressure under working loads. With that kind of equipment, we are very capable of making repairs, whether it’s on the pump or replacement of the PTO (Power Take-Off pump) itself.”  

They also do a lot of air conditioning work, not just in maintenance, but also in upgrades. “A lot of the older highway department machines did not originally come equipped with A/C; 20-30 years ago, you just rolled the window down and stuck it out,” Tomlin laughed. “We had a street sweeper through here yesterday where we installed an auxiliary rooftop A/C unit. It came as a kit, but we still have to fabricate A/C brackets, mount the compressor, route A/C lines and reconfigure the electrical.” 

He reports the only thing that’s been slow lately is parts delivery, being heavily impacted by COVID-19. “So we try to stock up with the normal stuff that we see day in and day out, those wear-and-tear type items.  A lot of the other specialty stuff we just order as needed. 

Meanwhile, his father Mike has started a virtual satellite store in Guthrie, Ky. With a single corporate client just north of the Tennessee border, the elder Tomlin is back to his roots, working out of a mobile service unit.  

“It’s a little bit easier [for dad] to manage one customer versus 50 customers, and depending on the season, they always seem to have quite a bit of work up there for him,” Tomlin reported 

“I would like to expand up in Kentucky,” added Mike Tomlin himself, having just returned from the Bluegrass State. “I’m normally there 10 months out of the year, 12-14 hours a day.” 

“Expansion as always is in the back of our minds,” his son continued. “We’re on a small piece of real estate here and there’s only so much that we can grow. But besides overcoming the obstacle of hiring personnel and stuff like that, I think there’s definitely enough business to possibly have a satellite shop up in Kentucky. Meanwhile we’re trying to make sure that the work that we’re putting out is proficient and efficient.” 

About the Author

Robert Bravender

Robert Bravender graduated from the University of Memphis (TN) with a bachelor's degree in film and video production. Now working at Masters TV, he produces Motorhead Garage with longtime how-to guys Sam Memmolo and Dave Bowman. Bravender has edited a magazine for the National Muscle Car Association, a member-based race organization, which in turn lead to producing TV shows for ESPN, the Outdoor Life Network and Speedvision. He has produced shows ranging from the Mothers Polish Car Show Series to sport compact racing to Street Rodder TV.

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