5 Nov 2013

100,000 trouble free miles

The title says it all. Up until that magic number of miles Shifty has never needed  a day-interfering, unexpected trip to the dealer.

Apart from the suspension coil spring that recently broke due to corrosion and a re-gas of the air conditioning system earlier this year nothing other than routine and preventative maintenance has been required.

Shifty's just recently had an "AB" service - inspection + oil change. It had two new tyres too - two Dunlop SP FastResponse. They replace a Dunlop SP01 and SP30 Shifty had on the rear. They were down to 3mm of tread remaining which is the recommended depth for changing. Legally it can be almost half that but the loss of grip and poor water shedding makes me nervous. 

With the winter season coming, having more tread depth equals better grip.
I'm also glad to get rid of the two different models of tyres on the back. I prefer same models all around, if possible, or at least the same model across the same "axle". The SP30 also had a higher rolling resistance than the SP01 so it's nice to move to a solution with the same low resistance all  around.

Ideally I'd have gone for Yokohama BlueEarth AE01which have been on the front for the last 25K miles but they weren't in stock from local suppliers with fresh supplies expected in a months time. Needing something sooner, I went for the Dunlop SP FastResponses. These have better rain performance than the Yokohamas and the same rolling resistance and are 1 dB quieter at 68dB.

Shifty now has the Yokohamas on the back and the new FastResponses on the front. The Yokohama had lost 4mm of their tread since getting them so still have another 1mm left to get through before replacement is due. Now they are on the back, free wheeling wheels they should wear less than being on the driven wheels, so we should get more than the 6000 miles out of them than if they had remained on the front.

Good stuff over .. now the not so good. 

My  untroubled time with Shifty had to end some time.  And it my luck changed when driving to work. At about twenty miles into my twenty-five mile commute, whilst gently braking (I usually brake gently as a rule) I heard noises. A chirping sound above about 20mph that turned to a loud-ish clicking from 5mph down.

Apart from these odd noises there was no difference in the performance of the steering. brakes or engine power. I stopped and did a visual inspection and could find nothing obvious. After checking over, I selected some residential side streets to determine the extent of the issue. It seemed only occur whilst braking.

Given that my partner was taking Shifty to her work the next day, a 120 mile round trip and that she'd be working late, I decided that the fault needed immediate analysis.

I took the day off work and drove Shifty extra cautiously to my regular dealer which, thankfully, accepted Shifty even without an appointment.

I retired to a local cafe awaiting the news of their analysis whilst surfing for what a clicking or clunking sound whilst braking could be.

What it turned out to be was quite unexpected and a testimony to the experience and quality of the mechanics at my Honda dealer. They traced the noise to the driver's side, outer,  constant velocity (CV) joint. There wasn't any play due to wear in the joint, the protective rubber boot was undamaged and securely attached but nevertheless enough of the molybdenum grease had come out of the joint into the boot to cause the joint to have insufficient lubrication. The effect of this was the chirping and clicking noise.
Oddly noises from CV joints usually occur when accelerating and usually with the steering turned to the left or right. I didn't have any noises except during the final stage of braking.

I wonder whether hearing this is down to a side affect of iShift clutch operation? Perhaps the clutch continues to be engaged closer to the point of stopping than a manually operated clutch would be, i.e. the wheels are still driven almost to stopping hence the noise?

Regarding lasting damage, whether the relatively short length of time that this problem was unnoticed affects the lifetime of the joint only time will tell. Hopefully it was caught soon enough.
With fresh grease added the noise ceased immediately and has not returned in the 250 miles driven so far.

Ending on a more positive note, over the last 10K miles the average fuel economy has been over sixty miles per imperial gallon.

That's been over the summer and into autumn... well done Shifty.