Q: My 2010 Tacoma 4x4 Double Cab has a condition my dealer describes as "driveshaft bump." When stopping or starting, it feels like the brakes grab or release and send a shudder through the truck. The Toyota dealer originally checked the brakes, which were OK. Using the A/C makes the problem more noticeable. I took it back to the dealer. They road-tested the truck and found the driveshaft bump. They can't tell me what's causing the problem, but said Toyota is developing a fix. This started about a year ago.

A: It sounds like the Toyota technician involved has opened a case with Toyota technical support, and tech support told him the engineers are aware of the condition and working on a repair or modification. This can be frustrating, and getting an accurate timeline for the repair is not going to happen. In some cases, where the manufacturer decides the condition may be considered a normal characteristic of the driveline, you'll never get an answer. But hang in there -- a fix may be coming soon. In the meantime, here are a couple of suggestions: Ask your service advisor at Toyota if your Tacoma falls within the VIN range for recall SC-A0D. This recall involves inspection and/or replacement of the front driveshaft due to cracking from a production defect. Regardless of the recall, ask them to fully inspect front and rear driveshafts, joints, and the rear support bearing. I've seen similar cases on other vehicles where the condition was caused by binding of slip joints. On your Tacoma, the rear slip joint is located at the center support bearing, and the front midway on the shaft. Nicely ask them to remove the yokes and thoroughly grease the splines. It's worth a shot!


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