lexuskim

Hi all, I've been gone for a while and missed you. My 97 LS400 has been jumping when I put it in reverse and then drive. It has always done it a small bit for 2-3 years, but in the last 2 months"ish" even more. Nothing else has changed or is different. It was in the shop for coolant pipes and cross over pipes a few months ago, but nothing else. It's driven 3-5 days/wk, for 8-15 miles and garage kept in North La. Any thoughts? As always, thank you and God bless!

LScowboyLS

can you describe this "jumping" a little more descriptively?

dc893

Is it like it really wants to go forward when put into gear? Mine has done this since I have owned it. I think it could possibly be the transmission mount or differential cushions. I plan on doing the transmission mount soon since it is the cheapest and easiest to do and only $66 shipped from Sewell.

http://us.lexusownersclub.com/forums...tial-bushings/

lexuskim

When I put it in gear reverse or forward, it's like a horse jumping before it's suppose to. dc893, you said your's has done this since you've owned it. Can this harm anything? Thank you.

LScowboyLS

what is the idle speed when you shift the gears like this?

dc893

Does yours do it at normal idle at about 600RPM also?

lexuskim

Idling speed is about 1500RPMs when I put it in gear. It's usually cold.

LScowboyLS

Idle speed should only be that high for less than 30 seconds after start-up, it should quickly drop below 1000 and idle around 650 as soon as it is fully warmed up. - if it is staying up at 1500 for more than 30 seconds, you have another issue. (not a transmission problem)

The transmission should never be shifted into gear when stopped at an idle speed of over 900 rpm, it is not good for it.

Stereorob

old car with old car problems. tranny mount is prob collapsed. its normal on these and wont affect the performance of the car at all. my 90 Ls400 had this problem and so dose my 95. i drove my 90 for 8 years and it never hurt it.