Hello, this is my first time ever joining a forum. I have 1998 SC400 with about 180K miles on it, apart from oil change I did and timing belt change soon, what parts need a refresh? Just for reference this has car has not been modified other than some rims and a cat-back exhaust. I had it inspected by a shop called Made in Japan who exclusively serviced the vehicle for the previous owner who was an older gentlemen, and they advised me to replace the front control arms. I already have a set of Figs Engineering OE replacement arms on the way to switch out the old ones. I assume it is an older car most of the suspension components need to be replaced. I am aware of most of the failure points of the SC, especially the power steering.

Id like to be pointed generally in which area I should focus refreshing. I noticed that when I shift into Drive or Reverse the car kind of clunks, however it is only exclusive to when I first start the car. The car shifts perfectly fine under normal driving conditions. Maybe transmission mounts? Also it kind of hesitates to accelerate after a stop, not sure if that's the nature of the 5-speed and it just being older or is there something I can do to make it more responsive?

I know it is a lot to ask but if anyone has a a lot of experience with these cars I would appreciate some pointers. I fell in love with the car as soon as I found out it existed. I maintain this car as much as possible I would just like to bring it at if not close to new in terms of mechanical feel.
Thank you for your time.

 

Sweet looking ride. How cold is the car when you shift out of gear? I shift out of P below the last mark on the temperature gauge and it becomes jumpy, damn near like a tank moving and rocking. If I allow it to "warm up" just above the C mark it will shift slightly better on that first shift to Reverse or to Drive. My engine/transmission mounts have about 8,000 miles on them, according to Lexus maintenance records.

Hesitation on stopping maybe a variety of things. If you do the California rolling stop, you may be catching the transmission into a downshifting position and increasing pressure may cause it to hesitate to shift in the other direction. My 07 Tundra does this and it's a newer 6spd at 330am California rolling stops away since there is no one else on the road. If you do a full stop and it's hesitating, maybe have it inspected at the shop, or check the transmission fluid level once it's at operating level and see if it's low. As per preemptively replacing parts suspension parts may be go with polyurethane bushings will probably help you get the car feeling tighter again. Inspect shocks and struts, as they often get overlooked and your issue may be more related to them than control arms. If you replace components, it's more work, but if you DIY, I would replace a part at a time, instead of multiple parts at the same time, in case you develop a problem you're not looking at 15 different places. If a shop is doing the work, then do it all at once, but if you develop an issue, you'll be looking at 15 different places for the issue

As far as replacing parts I'm more along the lines of, if it ain't broke, don't fix it. Otherwise, you won't enjoy your car as you will spend more of your time and money repairing and replacing stuff. Set a shoe box aside and put money inside for the time you'll need to replace parts and do it when it breaks. Odds are you will probably sell the car before it really breaks down and you'll have a good amount of money to go on a vacation with your significant other. Best of luck and enjoy your ride

 

Like mentioned above, it's worth checking the tranny fluid level, and if unsure what's in there, replace with Toyota Type T-IV.

I also have a DWP '98 SC400, and as much as the 5-spd A/T is an improvement over the '92-97 4-spd's, I never liked how slow it is to apply power on rolling starts and downshifts. I recently started playing with the ETC Power mode, and wow! I had only briefly tried it over the years, having understood it to mostly just make the shift points more aggressive. IMO, the shift points are already plenty aggressive in regular mode -- great acceleration from a stop -- so I always left it in regular (or Snow, when applicable).

I was researching ways to improve on the drive-by-wire response, and everything basically said nothing can be done, short of custom ECU solutions. (There is what looks like a throttle cable on the '98-00 engines, but it isn't the primary control.) So, I tried Power mode on a whim, curious if it would help the down-shift points in any way. What I found is it eliminates the vast majority of the DBW delay, and actually makes the car borderline skittish when giving it throttle at low speeds. It's great. It isn't quite as immediate of a response in the mid-range as a M/T would be, but about as close as any '90s slush box can be expected to be.

Between that and my recent mod to default Traction Control to off, it's a remarkably more enjoyable drive, having all that 1UZ power on tap at all times.

 

Have them do the serpentine belt/tensioner/pulley during TB service if you don't know if they've ever been done. Also do the crankshaft seal and thermostat. Camshaft seals might be overkill if they're not leaking but it'll add quite a bit of labor (have to pull valve covers and remove camshafts) to do those. That'll cover the front of the engine for a while.
The clunk is probably the 2 motor mounts and 1 transmission mount.
After that I'd just do fluids like power steering/transmission/diff. Then it's more quality of life stuff like pulling the trans pan to increase the solenoid pressure or replacing speakers/worn interior bits.