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Engine mount replacement swaps the rubber or fluid-filled mounts that hold the engine to the frame and soak up its vibration. When they crack or collapse, you feel it: shaking at a red light on Foothill Blvd, a clunk when you shift into drive, or a jolt when you step on the gas. Route 66 Auto Repair in Upland load-tests each mount with the engine running and watches how far it moves. The written estimate lists only the mounts that failed.
What are the signs of a bad engine mount?
- Strong vibration through the steering wheel or seat at idle in drive
- A clunk when shifting between drive and reverse
- The engine visibly rocks when you rev it in park
- Dark fluid near a hydraulic mount
- Exhaust or hoses rubbing because the engine sits lower than before
Why do some mounts cost more than others?
Basic mounts are rubber bonded to metal. Many newer cars use fluid-filled mounts, and some use electronically controlled or vacuum-switched mounts to smooth idle. Those cost more and can set warning codes when they fail.
Front-drive cars also have a torque strut or dog-bone mount that limits rocking. It wears fast and is often the source of the clunk. The transmission mount works with the engine mounts, so we check it too; see transmission mount replacement.
Our engine mount replacement process
Step 1: Road test
We feel for vibration and clunks in real driving, including the shift from reverse to drive.
Step 2: Load test
With the brake held, a technician watches each mount move under light throttle in drive and reverse.
Step 3: Inspect
Mounts are checked for cracks, separation and fluid loss, with photos of any failure.
Step 4: Replace
The engine is supported, the failed mounts are replaced, and bolts are torqued with the engine at rest.
Step 5: Verify
A second road test confirms the vibration and clunk are gone.
What's included in an engine mount replacement
Included on the work order
- 01Road test before and after
- 02Load test of every engine and transmission mount
- 03Photos of failed mounts
- 04Replacement mounts as approved
- 05Torque to spec with the engine in its resting position
- 06Check of nearby hoses, wiring and exhaust for rub damage
Is an engine mount replacement need-now or need-later?
Need now: call
- A broken mount that lets the engine lift or shift hard
- Hoses or wiring rubbing because of engine movement
Need later: book
- Mild idle vibration with mounts still intact
- A small crack in the rubber with no separation
How pricing and timing work
Access varies widely. Top mounts are often quick. Lower mounts on some front-drive cars require lifting the engine and removing other parts. Fluid-filled and electronic mounts cost more than plain rubber ones. Your written estimate lists each mount and its labor. AAA members save 10% on parts and labor, up to $75. Many mount jobs are same-day when the board allows; call (909) 608-7699 before you drive over.
After new engine mounts
The car should feel calmer at idle right away. New rubber may take a short break-in period to settle. If a clunk remains, the cause may be in the suspension or driveline, and we look there next. See our suspension and steering services if needed.
Frequently asked questions
Can a bad engine mount cause vibration at highway speed?
Sometimes, but highway vibration more often comes from tires, wheels or driveline parts. Mounts usually show most at idle and under load. We road-test to separate the causes.
Should all engine mounts be replaced at once?
Not automatically. We load-test each one and replace the ones that fail. When one fails, the others work harder, so we note any that are close.
Is it dangerous to drive with a broken engine mount?
A single worn mount is mostly a comfort issue. A fully broken mount can let the engine move enough to damage hoses, wiring or the throttle linkage, so it should be fixed soon.