2007.5-2010 Chevy Duramax LMM Exterior Parts

Exterior work on the 2007.5-2010 Silverado 2500HD and 3500HD

When GM moved the heavy-duty pickups to the GMT900 body in the middle of 2007, the Silverado HD got new sheetmetal, a new cab structure and the LMM under the hood. The cab and bed bolt to a hydroformed frame through rubber isolators that GM lists with the suspension as vibration-isolation parts. Configuration decides most of what fits out here. Regular Cab Long Box trucks ride a 133.0 in wheelbase, Extended Cabs run 143.5 or 157.5 in, and Crew Cabs run 153.0 or 167.0 in. A 3500HD came single or dual rear wheel, and the dually measures 95.9 in across where the single-rear-wheel truck measures 79.9 in, with overall length anywhere from 224.7 to 258.7 in depending on cab and box.

What fails and why

Exterior trouble on these trucks is mostly age rather than design. The rubber body and cab mount bushings deteriorate over time, and owners feel it as cab shake, clunks over bumps and the body sitting low against the frame. That pattern follows age, not mileage, so a garage-kept Silverado can need mounts as badly as a truck that has worked every day of its life. Past the mounts there is no documented LMM-specific exterior failure: a bent step bumper, a rattling plate bracket or a lower splash shield taken out by a curb are the ordinary wear of a used HD pickup.

Stock replacement vs. upgrade

OEM-style rubber mounts put the truck back the way the factory had it and keep the cab quiet. Firmer replacements are also made for 2007.5-2010 trucks, in polyurethane and in silicone, and they tie the cab to the frame more directly. That suits a truck that tows heavy or sees a job site; the trade is that more of what the frame is doing reaches the seat. The bolt-on pieces in this section are a different kind of decision. A roll pan, a license plate bracket, sled stops or a shorter antenna are appearance and function choices, not repairs, so pick them by how you use the back of the truck.

What we carry

Big Hitch Products covers the rear of the truck: a steel roll pan that includes a license plate light kit, a flip-up license plate bracket, a bolt-on plate mount bracket, and clamp-on sled stops in below-the-roll-pan and behind-the-roll-pan versions. S&B builds the silicone body mount kits, split by cab — one part number for Regular Cab, another for Extended and Crew Cab. Wehrli Custom Fabrication adds a lower splash shield kit listed for 2001-2010 trucks and a billet stubby antenna. The rest of the Duramax catalog for this platform sits in the neighboring sections.

Fitment notes

Start with the body, not the model year. A 2007 Silverado HD can be a GMT800 Classic with the LBZ or the new GMT900 body with the LMM, and exterior parts do not cross between them. Body mount kits are ordered by cab configuration, so know whether the truck is a Regular, Extended or Crew Cab first. Rear-of-truck parts depend on what is back there now — step bumper, roll pan, factory hitch — and dual-rear-wheel trucks differ from single-wheel trucks in rear width and fender shape. Several of these part numbers list a year range wider than 2007.5-2010, so read the fitment line on the listing, use the fitment checker on the product page, or call and we will verify by VIN.

Frequently asked questions

Will 2007 Silverado HD exterior parts fit my 2007.5 truck?

Not reliably. The 2007 Classic HD is the previous GMT800 body, sold alongside the redesigned truck and fitted with the LBZ, and exterior parts do not interchange with the new body. The GMT900 truck is the one that came with the LMM. If you are not certain which you have, send us the VIN and we will confirm it before anything ships.

How do I know which S&B body mount kit I need?

By cab length. S&B lists one silicone body mount kit for Regular Cab trucks and a separate kit for Extended and Crew Cab. Count doors to place yourself: two doors is a Regular Cab, two full doors plus smaller rear doors is an Extended Cab, and four full-size doors is a Crew Cab.

Are worn body mounts what I feel as cab shake?

They can be. Deteriorated body and cab mounts show up as cab shake, clunks and the body sagging toward the frame. Because the mounts are visible from underneath, they are worth ruling in or out before you start chasing a shake through the steering, driveline or tires.

Can you install a roll pan or a set of body mounts?

Yes. We are a diesel shop in Wildwood, Florida with our own bays, and we install what we sell. Rear bumper-area work and plate light wiring is quick. Body mounts take longer, because the cab has to be supported while the old bushings come out. Call the shop with your cab and box configuration and we will tell you what the job involves.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.