Case Study: Transmission Failure and Engine Damage Discovered During Repair

Written by the Motorplex Team
Offering fleet service shops and on-site repair services in Auburn and Spokane.

Every repair starts with a symptom, but sometimes the real story reveals itself only once the work begins. Recently, we had a repair at Motorplex by FleetEasy that turned out to be more than the customer expected. They brought it in with a drivability concern, which revealed two major mechanical failures: a faulty transmission and engine damage.

Comes in for Poor Drivability and Acceleration Loss

The vehicle, a high-mileage van with approximately 240,000 miles, was brought in for diagnostic evaluation due to issues with acceleration and overall drivability. Early inspection quickly pointed toward a serious transmission issue. Technicians found that the transmission fluid condition was severely degraded and looked like thick black coffee or burnt chocolate milk.

This can occur when the automatic transmission fluid burns, leading to serious internal contamination. Plus, metal debris was found in the transmission pan, including clutch material on the magnet and metal chunks at the bottom. It looked like the transmission needed replacing.

Transmission Failure Confirmed and Replaced

After the inspection, the estimate was approved to proceed with transmission replacement along with spark plug service and related components.

Once parts were ordered and received, technicians began taking things apart. The suspension was removed, and the CV axles were removed to access the drivetrain. The transmission was then removed from the vehicle, with only a few bellhousing bolts and mounts initially holding it in place.

The failed transmission was replaced with a new unit, and installation began immediately afterward. The replacement process included mounting the new transmission, installing mounts, and reassembling surrounding components. Technicians continued rebuilding the suspension and drivetrain components over the following days as additional parts arrived.

Additional Findings During Spark Plug Service

While the transmission replacement was underway, technicians also began spark plug service and upper engine disassembly. They removed the upper intake plenum to access the ignition components. All coils and spark plugs were removed, though the process revealed additional complications when two coil bolts broke off in the front valve cover.

Spark plugs were successfully replaced, and coils were reinstalled where possible. However, further inspection was required due to the damaged hardware and these added issues.

Major Engine Issue Discovered

While continuing diagnostics, technicians identified a significant internal engine problem. A damaged cam lobe was found on the right-hand exhaust camshaft at cylinder 6.

This discovery changed the scope of the repair significantly. The issue showed damage to the internal valvetrain. We recommended replacing the camshafts and at least one rocker arm on the right-hand bank. We also needed to replace the timing chain components and tensioners due to the nature of the failure and mileage on the engine.

The repairs on this van were really blowing up! We explained everything to the customer, including the estimated cost for further engine repair work.

Customer Direction and Repair Strategy

What would you do? Continue investing in this high mileage vehicle (remember, the transmission was just replaced!) or call it and move on?

We showed the customer their options: completing full engine repairs or continuing operation with known damage. They also considered the possibility of running the engine until failure and addressing it at a later time.

Ultimately, the customer requested the vehicle be reassembled in its current state after understanding the extent of the damage and potential risks associated with continuing to use the van. They decided not to go ahead with the major engine repair.

When Needed Repairs Are Too Many

It’s unfortunate when repairs and costs seem to get on a runaway train to more complex problems, but it does happen with older, high-mileage vehicles. We are there to explain the options, provide recommendations, and ensure the customer makes the right decision for their vehicle, budget, and business.

At Motorplex, transparency in diagnostics and repair planning ensures customers understand not only what is failing, but what may still be ahead.