jimaleg

I was looking at the scheduled maintenance regiment for my SC430 and I noticed all the fluids required periodic changing (brake & coolant every 30K, differential every 15K and oil every 5K) but no mention is made of steering fluid. I know brake fluid is important; especially to change at least every 2-3 years (if you don't hit 30K b4 then) but I was surprised no mention of required periodic Steering fluid changes. I know the linkage is required to be checked as part of scheduled maintenance. Is steering fluid not as important or is it a mechanics call? If so, any suggestions on how long/miles one should change steering fluid?
Unrelated: I have an 03SC with 115K. I did my1st timing belt & water pump (it had a slight drip) at 9.5 years and 75 K. It's been 9 years since the timing belt/water pump and I'm wondering if if I should wait another year? Amazingly I didn't see my mechanic replaced my thermostat during the best/lpump change (but maybe it's included with the water pump?). I've read about timing belts going well beyond the 90K/7 year requirement and I appreciate time can be as hard on a belt as miles so my question is do it now or wait? In addition to what appears to be an original 03 thermostat, my last coolant change appears to be when I did the timing belt 9 years ago (I know bad me). If I don't do the belt should I do the coolant even though I'll do the belt at most in 1 more year and does it make sense a thermostat could last 18 years? Unfortunately the garage is usually outside year round in Northern VA. Thanks!

mandyfig

It appears that power steering fluid is not as taxed as the other fluids hence it is not in the mandatory replacement list, I think.

Some of us, we just do a drain and fill (means using a baster or whatever, we suck the power steering fluid in the reservoir and then refill fluid to full. We normally use a baster for sucking it up. I personally do it twice a year and I check the color or the fluid every couple of months. If I see some dullness, I suck it up and refill.

Try it.

jimaleg

so it's not a complete flush but a partial flush that is done with regularity such that the fluid is kept in better shape than if not done? I'm guessing the resevoir only holds a portion of the total brake fluid. How much do you get in each time you do it? 1/2 quart if that?
Also any reason a thermostat would not be replaced with a timing belt and water pump? I guess if the thermostat is still working I should be worried but I also understand it can pop at any time in which case, I'll have an over heated engine on my hands.
Last and not least, I only have 40K and 9 years on my timing belt & water pump. Should I chance it another year or 2?

jimisbell

If it aint broke dont fix it.
The army and air force found this out durring WWII and it was such valuable information that it wa s classified SECRET. They found that engine failures on aitplanes often happend just after scheduled overhaules based on time of operration so they ended the practice but because it was SECRET it didnt get out to civilian aircraft mechanics till just recently.

But the timing belt is anoher story, The belt ages and the result of failure is catistrophic so not worth the chance.

If its working dont disturb it unless failure is not an optiion

LeX2K

I swap PS fluid every few years just because. It's cheap and easy. Thermostat is entirely a how many miles replacement deal, I find after about 200,000 miles they can start to get lazy. Very unlikely you need a timing belt or any of the components replaced.

voloc22666

after i changed my timing belt (i guess the second one for my car, the one in there was a replacement already), i had to change all the pulley. The SECRET wont apply to them, as i pressed out the bearings and looked inside, they were dry and rusty. And believe me, i KNOW what happens when the serpentine belt pulley gives up on the highway..I wonder is any of the car manufactures expect their cars being on the road for more than 10 years or really care about that..

Wilson2000

Many moons ago, I used to change my thermostats every 2-3 years when the coolant change was due. But, now long life coolants go 5 to 10 years (red-5, pink-10), thus, I rarely change t-stats anymore. Plus, Toyota/Lexus OEM parts are so good, I don't feel the need to change them preemptively anymore.

I do a partial change of the power steering fluid (ATF) every-other oil change, or so, depending on how it looks.

I stretch my timing belt interval 30-40% based on time (I drive low miles). After doing a number of TB jobs on Toyota/Lexus, I have yet to see one look worn. Usually, a water pump or pulley (in the TB train) will show signs of failure first, prompting me to do the TB job simultaneously. Otherwise, if you are 100% risk adverse, do it now!