lownfastsc

Hey folks, found a sweet deal on a 1998 sc400 and just couldn't pass it up. It has about 130k miles and is hella clean. However I have no evidence that the timing belt has been replaced, and it makes me a little nervous to be driving it around. Am I just being a worry worm? lol. Is their an easy way to inspect it, or a way to tell its been replaced? There is no sticker in the engine bay, nothing on the carfax of a recent service, and nothing written in the service records in the manual. I need your knowledge/advice before I spend 1000+ on getting it replaced. I'd do it myself but it would be my first timing belt and id rather learn on a non interference motor. So I figure I better just spend the money and have a professional do it. What do you guys think?

SC400slide

iTrader: (11)

Firstly check out the service records online at Lexus drivers .com, all dealership records will be recorded there. Otherwise, all you have to do to check the belt out is remove the "V8 32 valve 4 CAM" plastic panel, the "1UZFE" plastic panel, then finally the plastic piece with the lines/grooves on it. Under this is where the t belt will be.

May not be the same with the VVTi's, but should be pretty close.

lownfastsc

Wow, thank you very much sir. There is 6 pages of records for my car, turns out the timing belt was replaced at 78k miles in 2008... So I guess that's that. lol. Next concern of mine is that there is a pulsing vibration when driving at highway speed and it changes depending on which way your turning. I'm guessing it has something to do with the lug nuts being super tight. I was using the stock lug wrench with a 4' cheater bar. Got a few off but ended up twisting that lug wrench about 90 degrees. lol. And on top of that there is no anti-seize on them, I won't be surprised it i snap a few studs.

bigwhite

Dont think you should put anti-seize on lug nuts, just proper torque.

lownfastsc

^ Its debatable. Some people say it throws off torque spec, but you can compensate. And they definitely need something when you can't start them by hand, or when you need a huge breaker bar to remove them after they have been on the car for awhile. Greater change of damaging something when there stuck on there imo.

Ramblerman

Lug nuts should be tightened in a sequence pattern on your wheels, always use proper torque specs, never over tighten as this can warp things(rotor/hub) & and never use anti seize on your studs as this can cause them to possibly loosen.

Ali SC3

iTrader: (10)

sounds like you need a torque wrench. set it at 100 and then go to town on the lugs, be sure to stop when it clicks.

lexsc3

Second that you need a torque wrench. I wouldn't put anti-seize on lug nuts, you rather have a lug nut that take alttle more effort to get off than one that might work its way off. Figure out the thread and pitch of the studs and get a die and a tap the same size, chase all the studs and lugs to clean them off. I do this on my audi ever so often because it has lug bolts and the different size of wheels between my winter and summer setup have the lug bolts going into the hub different amounts. It will make a world of difference, that little bit of grab when putting them in by hand goes away and they feel like new. Its cheap and easy to do.

lownfastsc

I use a torque wrench... Using a die may have been a better choice, however I don't think using anti-seize is going to make my lugs start falling off. But, back to my question about the vibration.. I believe it is drivetrain related now, its only noticeable when over 50mph and it gets stronger when under load, like when going up hills. Also, just today idk if its related but I stopped at a light and heard a quite grinding noise so I rolled forward a bit and it stopped. The engine was fairly cold, had been running for about a minute. Anybody got ideas of what it could be? Trans I guess?

lexsc3

First thing i would check is all the brakes to make sure none of the slider pins are stuck. A pad slightly dragging can cause what you're experience. These slider pins get stuck all the time. Pull the pin, clean out the hole, regrease, and replace the pin or boot if damaged. Then if that doesnt work start with the easy and cheap things like if the wheels are balanced and get the alignment checked. Its most likely something simply, don't go dumping money into possible drivetrain stuff.

lownfastsc

Thank you, I will look into that this weekend and let you guys know what I figure out.

lexsc3

Also make sure all the calipers are good and don't need to be rebuilt. A stuck piston in the caliper would make a brake pad drag too.