Required services

Hi all,

I've had a Leaf since 2011, and just lost my 4th bar (56000 miles). The dealership did the diagnostic check and I qualified for a new battery (whoo hoo!) At the same time as telling me this, they said I was behind on services. They said my transmission fluid (or maybe they said something else) was dirty. This didn't make sense to me, but wanted to see what you all had to say about this...I'm guessing this is an upsell for the unsuspecting. They also said my brake pads were rusty (guessing from non-use), and I've already read about the brake fluid replacement "scam"

Any information on the "dirty" transmission would be helpful.

Thanks for any information you guys have,
Jeff

Not sure what the replacement interval for the reduction gearbox lubricant is; I don't think the maintenance guide ever gets there by 120,000 miles. It does call for inspection of the oil though, but that seems to be to make sure there isn't leakage. The gear oil would seem to have a fairly easy life; the gears are permanently engaged and no shifting. Gear oil will always have a silvery appearance after it's been in service, in my experience. There should be a magnetic drain plug to gather up any particles of damaging size.

The yearly brake flush recommendation is excessive, imho but after 4 years I'd say it's a good idea. I usually do it every 2 years. I had to fix a vehicle that went far too many years without a flush. It wasn't pretty. You can get a test kit if you're the type who insists on maximizing the dollar value of your brake fluid. Kind of depends on the average humidity in your area -- conventional brake fluid is hygroscopic.

Not sure I understand about brake pads being rusty. Maybe he meant the brake discs (rotors). Sometimes they'll develop a light coating of rust after they've sat wet, but unless it's sat a really long time, the surface rust is removed just by braking a few times. If the rust is excessive you'll know it because either the pads will be stuck to the rotors, or you'll hear a lot of grinding noise when you brake. There are specifications for pad thickness, rotor thickness, etc..., which determine if replacement is needed.

With as little you use your brakes and brake fluid being hydroscopic, I came to the conclusion that it was likely an engineering recommendation and not a scam. I had it flushed by an independent repair facility at the recommended two years. The cost ran about the same as the Nissan dealers so next time I likely would take it to the dealer despite the hassle having service grading emails hosed at you over every tiny service. :lol:

Phoenix systems sells a different kind of brake fluid test strips, and they point to articles that may
explain the short (2 year) replacement periods that we are now seeing even on other makes of cars.
They appear to say that with modern brake systems that have individual control over all 4 wheels,
that there is more fluid motion, and more valves, and parts that the fluid interacts with ,which causes
the anti-corrosive chemicals added in, to not last as long, and that long before water in the fluid becomes
a problem the lack of corrosion protection becomes a problem. So they sell copper test strips to measure
the corrosion resistance of the brake fluid (more copper less corrosion resistant).

Yeah, I still think that three years is a reasonable, prudent interval, assuming they don't use Chinese brake fluid at the factory. I can understand that having a bad experience with an old car that wasn't maintained could make one wary, but that doesn't equate to a necessity for a new car being over-maintained. As for all that extra fluid wear associated with ABS and traction control, if this were the case with the Leaf, we'd also see people actually wearing out brake pads on a regular basis...

For our application, the brake fluid change interval has nothing to do with wear or heat like in a race car, but more importantly moisture absorption at a hydroscopic level. Even unopened brake fluid stored in a plastic container in a temperature controlled environment is contaminated after 1 year of sitting on a shelf. Just like air escapes out of a tire, moisture gets into brake fluid. Although, brake fluid stored in a metal container has a shelf life of 5 years. On a vehicle, moisture absorbed into the system will take out components like caliper pistons, master cylinders and/or the expensive ABS brake controllers(the mechanical valves). It's not fun having a brake caliper piston lock up or even worse a master cylinder failure(squishy pedal) but an ABS controller at thousands USD, have mercy. For example, one of the largest brake systems manufacturers, ATE, has seen a HUGE increase in ABS brake controller sales over the past 5-10 years because of the lack of this simple brake fluid service. Great for them, not for consumers.

I guess I'm just amazingly lucky that, in my moderately damp climate, my brake fluid was still ok after four years.

LeftieBiker said:

I guess I'm just amazingly lucky that, in my moderately damp climate, my brake fluid was still ok after four years.

Click to expand...

What makes you think it is okay? (BTW-only way to really test is to heat up a sample then watch at which temperature it starts boiling. And a sample furthest from the reservoir will be the most contaminated...soooo might as well just flush or suck with a MityVac ;-)

Another fun fact, every year brake fluid loses roughly 85F from its wet boiling point...quite a lot, especially if planning a trip with steep downgrades which may really heat up the fluid *eek* (probably not a major concern on a short distance commuter like a Leaf ;-)

I define "OK" as "No reduction in brake function (that would include sticky calipers and spongy brakes), and fluid passes hydroscopic and copper contamination test." My own theory is that a lot of brake fluid contamination is the result of the reservoir being opened often. I think that translucent reservoir bodies and dealer services that don't routinely involve opening the reservoir have done a lot to help the average brake system. IOW, I am not saying that you are wrong, but just that the experiences of Leaf drivers in all climates, as related here over 7+ years, don't support (with maybe one or two exceptions over the years) the idea that the Severe service schedule needs to be followed for brake fluid flushes unless the cars are actually driven in severe conditions...