I drove two Ford full size station wagons, a 68 and a 75, for over 250k miles each and never even considered changing out the transmission or diff'l fluids on a scheduled basis, and I'm pretty sure it wasn't on Ford's recommended schedule.
What has Lexus done wrong within the transmission design that would shorten the working life of fluids that normally last 100 to 120k miles?
ford full size station wagons are anything but smooth.
one of the best quality about a Lexus is it's smoothness. especially the transmission smoothness when shifting.
i'm sure u can get 100k on the car w/out a problem, it just won't be smooth and i mean, would u really do that to a nice lexus?
Nobody touches my transmission fluid, diff'l "grease", or brake fluids absent some sort of repair requirement. I'd be willing to bet that if Lexus put your old fluid right back and didn't tell you (maybe that's what the dealers do anyway!) you'd still drive away thinking the shifts were smoother.
Absent extraordinary heating or internal component failure the transmission fluid you drain out will be just as viable for use as the new stuff you put in. Same goes for Diff'ls.
You might want to check the level, "color", and smell, each time you change oil & filter but unless the fluid looks or smells "burnt" from having been over-heated (towing a trailer up a steep hill at full throttle, etc.) I wouldn't touch it.
i really think dealers try to get customers to do stuff on a regular basis. its like well...im do for a tranny change next week....i might as well get my brake and coolant changed too. i really think its more of a sales technique.
its like the timing belt thing...they said get it done this many miles every time...yet some sc's go 100k-120k miles without anything happening (30-60k past recommended intervals)....and thats not luck....if it were 10k above the recommended interval that might be luck....but when it can go 30-60k more...it proves that these engines dont need to be serviced as much as they say. i think as long as you keep the fluids to proper levels...nothing should ever happen.
Timing belts, like clutch disks and brake pads, are "wear" items.
We have ways of detecting or indicating when clutches or brake pads are near the end of their usefull life, but regretably that's not true (yet) of timing belts. It's not a matter of "will they fail?" but "WHEN will they fail?"
And yes, some timing belts may last throughout the life of the car, 200k maybe, but until we find a way to more accurately project when they have reached the end of the usefull life the best thing to do is abide by that 90k figure.
For months I've followed your postings where you wisely advise owners to skip unecessary ATF changes- so why are you telling them to blow $600, $800 or more to replace belts that go way past that 90K interval in regular use?
Most of my points on this issue have already been posted, so I'll try not to repeat myself (unlike some others on this forum, ya know? ), but I have yet to find anyone that has actually had a belt wear out and break on its own. A few mechanics have, but they see a thousand cars a year! That 90K "recommendation", which they set at the beginning of the production run of the V8, has turned out to be way too conservative in actual practice. Since a broken belt only costs you a tow job, changing the belt that often is pretty expensive insurance.
Transmission flush is much more expensive than replacing the fluid and is included in the major service. The cost of the fluid for our car alone is expensive. (indedent shop $175 vs. $300 at dealer)
The condition of the fluid has lots to do with how the car is driven, stop and go/highway, towing, and up/down hill. If the fluid is real dirty, it needs to be flushed. Usually there is no sign shows before the trans break down, so flushing or replacing the fluid is usually for insurance/maintenance purpose, not for better performance unless it's really bad.
Same with driving belt, it depents on how the person drive. Convervative driving can put lots of miles on a life of the belt.
Brake fluid: It should be flushed once every 2-3 years regardless, due to deposit of moisture. Believe me, you'll feel the difference. It also should be included in the major service. At one time i thought i had to change the abs pump on my other car which cost thousands. It turned out all i needed was a brake fluid flush for $75.
Not changing your tranny fluid is the most ridiculous thing I've heard... No.. you shouldn't change it just for the hell of changing it... thats really the case with every fluid in your car...
With Tranny fluid that color and smell are the most important things, but thats the case with most fluids... some of us who know cars, know that when 15K or 20K comes around, we check the color or smell of the fluid... then we decide to change it or not... But for most people who don't know this or can't tell... there are general rules of thumb...
they say change your oil every 3000 miles or 3 months... but if you haven't driven your car at all for 3 months... duh... you don't need to change the oil... but for most people its 'easier' to just keep a regular schedule so they DON"T forget to change these fluids...
IT IS ABSOLUTELY RIDICULOUS TO ME that people would tell others in CL that the tranny fluid doesn't need to be changed for 100K...
Tranny fluid starts out redish in color... once its brown, then change it!!!!!!! usually this happens around 25K for the standard driver... That means its burnt!!!!! For me I change it every 15-20K miles, since it fits easily when changing my oil.
If you push your car harder, it may 'burn' quicker...
My point is simple, don't compare old 1960 or 1975 tanks with todays cars.... Take care of your car!!!!! The car will still get from Point A to Point B, even if you don't change your tranny fluid for 60K miles (hopefully), check that dipstick... that fluid will be black...