Please Advice.

[Shyameetu]

Hello from Newbie to all Lexus owners and Gurus,

I am recent owner of 1991 Lexus LS400. It has 172000 miles on it. I am new to Lexus but long time DIYer of my other car and motorcycle. All I am trying to get advice from you guys and possible suggestions on repair. My questions are as below.

1. Car runs smooth, However drive becomes shaky after speedometer reads over 60. Please suggest where to look for. Nothing has changed in steering suspension by previous one and only owner. Engine oil changed before 6 month, Transmission/ deferential oil no record. Same for spark plugs too. I wonder timing belt lasted this long without changing it.

2. Are aftermarket parts from like rock auto and all works good? Trying be easy on my pocket and don't want to pay ridiculous price, but if there is no way then . Please Advice.

I am thinking about giving good tune up; Timing belt with timing components, Spark Plugs with wires, rotors and distributor caps, thermostat and coolant flush, engine, transmission and differential oil, fuel filter, air filter, etc. Am I missing something OR over doing anything please Advice.

Moreover, should I replace struts, control arm, tie rod (Inner/ Outer), Ball joint? What is ideal replacement milestone for all these?

If it were my Camry, I wouldn't let it pass 100000 without it. I love this car and feeling sad that it hasn't had chance to get recharged.

Thanks in advance.

[steve2006]

1) Check wheel balance.

2) Also consider Sewell/Park Lane Lexus for discounted parts.

3) Also replace water pump while changing cam belt and cam seals.

4)Check all suspension components but only replace what needs doing, bushing kits are available instead of replacing the whole component.

[Shyameetu]

Thanks! Steve for taking your time.

Ever since I have posted for suggestions I am counting viewers but at-last you broke that sequence . Today I went for wheel balancing and ask for check the tires and any potential issue relevant to symptoms. He confirms that wheels are good and balanced but he has seen, this kind of problem, due to worn struts. Also somewhere in the other thread it turns out to be drive shaft weight balance problem. I checked struts by pressing with my body weight to front and rear and there is no bouncing effect. what could be possibly wrong with struts? Any suggestions. Moreover, I will check drive shaft this weekend and see if I can found any balance weight flew off. Chime in, if there is another way to check struts to confirm the culprit. It would be much helpful towards my diagnostic process .

I am gonna change water pump and seals as well + just came across owners manual and in that, it is suggested to check valve clearance every 72000 miles. this one has 172000 so will do that also along with spark plugs.

[landar]

As for the shakiness, you might consider rotating tires, front to back to see if the issue persists. Also, when above 60 mph, try to determine if the shake is worse under acceleration or same when you let off the gas. You might also throw the gear shifter in neutral to help understand if the vibration is from the powertrain.

[Shyameetu]

Thanks! Landar,

I knew, I will have good amount of clues on how to troubleshoot issues with my lex from experts. I will check as you suggested and update information here as I get along with troublemaker.

[steve2006]

Good point Landar, could also be worth checking the motor and transmission mounts as they do break up.

Also have a look at the tutorials on www.lexls.com which I find very helpful.

[billydpowell]

I have owned 12 LS's and check valve clearance every 72000 miles is news to me... in replacing timing belt and w/pump cam seals and c/shaft seal, most kits come with the bearings, am aisin kit is as close to OEM as you can get.. more later, have to go.

[Shyameetu]

Hi Billy,

Thanks for suggestion on timing belt component kit.

Sorry! for the confusion on the valve clearance due milestone. It is due @ 72 months and not @ 72000 miles. You are right it indeed sound like news due to my quick sight to maintenance schedule. It is 72 months.

You have experienced 12 great LS and your suggestion would be worth to have. Could you please shed some light on other parts selection. I mean to say, spark plug wires, steering and suspension components,etc.?

Steve suggest to replace bushing if it is required rather then whole component but I believe from my personal experience that metal component has also tensile strength, which gets degraded by use under constant stress (Becomes little too flexible). I learn it when I replaced control arm and installed quick struts to my Camry. The car feels more rigid and confident. Which wasn't a case previously when I did only bushing and struts replacement. I may be wrong and it is total different machine.

[sha4000]

Changing the whole part can get expensive on these cars that's why he suggested just changing the bushings where applicable. The timing belt kits in Amazon are pretty cheap. As far as the bushings I would get most of those from an online dealer like Lexus of South Atlanta.

[Shyameetu]

Perfect!, Agree with that. I just want to make sure change bushing vs whole component difference. We are on same page. Thanks a lot. will surely check Amazon to save money.