cashvegas

My car was diagnosed by an independent shop (former Lexus techs) with collapsed engine mounts, and replacement recommended. I've been researching that issue; reading several posts about engine and tranny mount replacement, on this forum and several others. I've got a pretty good idea about the procedure involved, parts numbers, and cost. However, I wonder if my symptoms are actually severe enough to confirm that this is really an issue. From what I've read about what most other drivers experience, they seem to describe a pretty severe vibration in the steering wheel or shifter while at speed or when revving the engine in Park/Neutral at 1500-2000 RPM. While I can detect (what I would describe as) a slight vibration while revving (in Park) at around 2000 RPM, I wouldn't describe it as severe. Is it possible for the engine mounts to be worn out, but only have a slight vibration? Thanks in advance for any input!

timmy0tool

iTrader: (7)

welcome, and good job on researching all the info already on the mounts. it would be wise to let us know what year car you have and mileage. we can better assess your situation.

i always suggest to replace the transmission mount first as it's the main culprit in most vibrations (outside of the front strut rod bushings, not related to any mounts). it is also very easy to replace!

replace it first and i would say 90% of the vibes are mitigated. of course a bad trans mount almost always means your motor mounts are probably shot as well. trans mounts usually go about around 100-150k miles.

sha4000

iTrader: (1)

What's the mileage on the car? You can have someone rev the engine and watch to see how much movement it makes. It is supposed to move some but if it excessive you should be able to tell. If you have lots of miles I can almost promise you they are shot and will fall apart once removed.

sam12345

iTrader: (1)

Yes not.only possible but probable. My car felt normal (I thought) but changing the engine mounts (I had already changed the tranny mount) made a world of difference. I feel zero vibration at the steering wheel at idle. My mounts were not broken. Only had begun to seperate a little. It also made the quality of the car as you drive way better. It is amazing what a difference an engine mount can make. Use lexus mounts

cashvegas

Thanks everyone for the input, and my apologies for the delayed reply. I should have thought to put the year and mileage of the car (duh!). It is a 1998 LS400 that I bought nearly four years ago with 112K; now it has a little more than 172K. Today I took an hour+ road trip from north of Dallas to Fort Worth; it was all highway, and I really noticed the vibration seems to be getting more pronounced (I was running between 70-80mph). I tried putting the car in Neutral and coasting at speed, and that reduced it tremendously; which seems to me to point to the mounts (engine and tranny). I have already ordered an OEM transmission mount and will be replacing myself. I am still on the fence whether to attempt replacing the engine mounts myself or not (any thoughts?). I'm a pretty decent shade tree mechanic, and have jacks, stands, and a pretty good selection of hand tools at home. Otherwise, I might just pay a good indy shop to do that since they have the lift, professional tools, and the experience. Other than the parts, what would be a good estimate for the Labor portion of replacing the engine mounts? Also, that is the first I've heard of the front strut rod bushings issue; can anyone provide more details? Thanks in advance!

sha4000

iTrader: (1)

Definitely a doable job for a shade tree mechanic. The strut bar bushing would give you thumps over small bumps at slow speeds and probably is not your issue but at that mileage I'm sure they are worn too as well as ball joints. You can cross that road when you come to it though..

Here is the tutorial I used when changing my mounts.

https://www.clublexus.com/forums/ls4...placement.html

cashvegas

Well, I received the OEM transmission mount today; and had it installed in a little less than an hour (I took my time and moved deliberately; cleaning up parts underneath along the way). It made a very noticeable difference in how smooth the car is at idle and at speed. Now I can't wait to get the motor mounts done. I took a look at them while under the car today, and I am going to pass on doing the job myself. I have a very highly recommended indy shop in town that will do the motor mounts all in (OEM parts and labor) for $450; which is a good alternative to using my time and blood/sweat/tears. In the meantime, can someone tell me a little more about the "front strut rod bushings" that timmy0tool mentioned above; and specifically, are those something else that I should be replacing at this point (considering I'm doing the other things)? Thanks in advance!

sha4000

iTrader: (1)

Heres some reading.
https://www.clublexus.com/forums/ls4...ock-noise.html

sam12345

iTrader: (1)

450 is way too much, if it's someone who has done it multiple times before it should be less than 2 hours tops. So the labor should be less than 200. Took me less than 3 hours and it was my second time (did my gs400 before). A good mechanic should do it in an hour or so

billydpowe

iTrader: (1)

yep 450 is to much 2 hr job..
my mounts came out in 2 pieces
other photos are strut rod bushings AND they only are SUPPOSED to go one way see new package

Australian

I know my transmission mount is shot so I guess i may as well fix this too.

GH5T

I was recently quoted $760 parts and labor indy shop price my lcoal Toyota dealership estimate was $1235. I asked why so much and was told by the technician that his manual said that the front mounts required 8 hous of labor each to complete while the Trans mount only requires 1 hour. Has anyone tried the Roca brand mounts?

sha4000

iTrader: (1)

I would stay with the OEM mounts on this job. I tried aftermarket and had to immediately remove them and order OEM mounts.

hyperopt

Which aftermarket mount brand did you try?

billydpowe

iTrader: (1)

copied from Pure Drifter: i'll confirm this procedure is the same for all 95-00 LS400s.

I've posted up tips/tricks in other threads but i'll repost them here.

-Use a jack to manipulate the spindle to make removing/reinstalling the strut rod into the LCA.
-make sure you put the strut rods into their respective sides, THE ARMS ARE NOT THE SAME. they are marked L and R. The bushings are the same for both arms.
-Torque big bolts TO SPEC! otherwise your alignment WILL come loose or something important will work its way off... a $20 torque wrench is better than your wrist, i almost guarantee it.
-the OEM bushings HAVE TO BE PROPERLY CLOCKED! Refer to manual, I believe the "tabs" in the bushing have to be 90* perpendicular to the arm, pointing down.
-DO NOT TIGHTEN the adjusters until the car is ON THE GROUND!! You need load on the arms so they reach their resting position before you torque down the caster arms or you may experience bushing accelerated ear/tearing.
-Avoid poly bushings, or at least know what you're getting yourself in to.
+a 24-36" 1/2 or 3/8" drive breaker bar WILL save your life....
you can do it