# Diesel Engine Mount Repair in Upland > Heavy clunk or shake from your diesel? Route 66 Auto Repair in Upland inspects diesel engine mounts, shows photos of any tear and quotes the repair in writing. Source: https://route66autorepairshop.com/diesel-engine-services/diesel-engine-mount-repair Updated: 2026-09-17 Business: Route 66 Auto Repair, 1775 W Foothill Blvd, Upland, CA 91786, (909) 608-7699 Hours: Monday to Friday 8 AM–5 PM, Saturday 8 AM–2 PM, Sunday closed **TLDR:** A **torn engine mount** lets a torquey diesel shift and clunk. We check each mount under load and **photograph the damage** before quoting. Diesel engine mounts are the rubber and steel blocks that hold a heavy diesel to the frame and soak up its vibration. Route 66 Auto Repair in Upland inspects and replaces worn diesel mounts on pickups and vans. Diesels shake more than gas engines and make more torque, so a torn mount shows up fast as a clunk or a buzzing cab. Our ASE-certified technicians photograph any damage and quote it in writing first. ## What are the signs of a bad diesel engine mount? - A thud when you shift into drive or reverse - The engine visibly rocking when you rev it in park - Vibration through the floor and steering wheel at idle - Clunk when you pull away with a trailer - The fan shroud or hoses rubbing because the engine sits lower ## Why diesel mounts wear out A diesel twists hard against its mounts every time you accelerate, and more so with a trailer. Heat from the turbo and exhaust bakes the rubber on the hot side. Oil or fuel leaks soften it further. After enough cycles the rubber splits and the metal plates can touch. A collapsed mount also stresses everything bolted to the engine: exhaust pipes, intercooler hoses and the fan. If you see a cracked [diesel exhaust system](https://route66autorepairshop.com/diesel-engine-services/diesel-exhaust-system-repair) joint, a sagging mount can be the reason. ## Our diesel engine mount repair process 1. **Load test:** With the brakes held, a technician watches engine movement in drive and reverse. 2. **Inspect and photograph:** Each mount is checked for splits, separation and oil soaking, and photos go on the repair order. 3. **Support and replace:** The engine is supported safely, the mount is swapped and bolts are torqued to spec. 4. **Recheck:** We repeat the load test and road test for clunks and vibration. ## What's included in diesel engine mount repair - Engine movement check in gear - Visual inspection of every engine and transmission mount - Photos of torn or collapsed mounts - Replacement mounts and hardware as approved - Torque to manufacturer specification - Clearance check for fan, hoses and exhaust ## Is it a need-now or need-later repair? **Need now:** - Fully separated mount or engine contacting other parts - Fan or shroud rubbing **Need later:** - Surface cracks in the rubber with little movement - Mild idle vibration from an aging mount ## How pricing and timing work Mount access varies. Some diesels need the engine raised and parts like the fan shroud or exhaust loosened. We quote the mounts that are actually worn, not the full set by default. If a leak soaked the mount, fixing the leak first protects the new rubber, and we will say so. The [diesel engine services](https://route66autorepairshop.com/diesel-engine-services) hub lists related work. ## Aftercare The shift into gear should feel crisp without a thud. Tell us if any new noise shows up on your first trailer pull. A matching [transmission mount](https://route66autorepairshop.com/transmission-services/transmission-mount-replacement) can wear on the same schedule, so we note its condition too. ## Frequently asked questions ### Is it safe to drive with a broken engine mount? For a short time, if the engine is not touching anything. A fully failed mount can let the engine shift enough to damage hoses, the fan or wiring, so do not wait long. ### Should all mounts be replaced at once? Not always. We replace the ones that are worn. If the others are close, we list them as need-later so you can plan. ### Can a bad mount cause a check engine light? Not directly. It can, however, stretch a sensor harness or crack an intake hose, which can set a code. --- Call (909) 608-7699 or visit https://route66autorepairshop.com/contact for a written estimate.