When I replaced the right rear tire at the dealer, they suggested me to replace the rear shocks and the left front lower trans mount. My question is: I don’t feel my car bounce and shake nor hear any noise. Is it time to replace them?
How would we know without seeing it? Take he car to a local independent mechanic and have them check out those areas. If they think it might be time to replace those parts it will be cheaper than the dealer. And a dealer is not the least expensive place to buy tires.
I had a 2005 Accord until last year, and I never replaced the shocks, nor did I need to. If your shocks don’t bottom out when you go over a rough spot, don’t worry about it.
If I remember correctly, my '06 Accord did have one rear shock fail. So, yes, it may be real.
Honda engine and transmission mounts are liquid-filled and over time start to leak. If one or more leak and collapse the engine will appear to run rough and vibrate.
I normally advise immediate replacement of the item and a careful inspection of the others. If not done soon, the others may face the same fate.
If the trans mount is starting to collapse it should be replaced. B/c otherwise it could result in hard to diagnose and expensive to repair problems later. It’s sort of unusual it would do that on a 2006 though. I checked all the engine and transmission mounts on my 26 year old Corolla recently, and they are all fine. Transmission and engine mounts tend to fail b/c of an aggressive driving style with rapid accelerations and aggressive engine braking. If that’s not your driving style, perhaps the problem is what Docnick suggests above, it’s a materials design problem and you just got unlucky. In any event, suggest to get a second opinion on that one. Don’t ignore it though. The dealership may have done you a big favor by spotting it. I’m, seeing roughly $50 for the part, and 1/2 hour to replace it, so it shouldn’t be overly expensive.
For the rear shocks, since you have no apparent symptoms in the ride, suggest to just monitor the situation. A couple of things you could do now: (1) ask a friend to drive along beside you and watch your rear wheels for any unusual movements compared to other cars on the road when you go over bumps; and (2) with your car parked in the driveway, look carefully at the tread of the rear wheels for any unusual wear patterns, especially cupping, as that can indicate the shock isn’t doing its job.