pachocco1

Ok now, my mechanic has finally solved the problem. It appears that the assurance I was given that a remanufactured driveshaft would be up to OEM new specs was unbalanced (pun). After focusing on other areas, my mechanic returned to the driveshaft as the possible culprit. While another 91 was in his shop, he did some process of elimination with the problem areas. Removing both axle assemblies (to eliminate the wheels as well) and still having the vibration. Removing driveshaft produced no vibration at all (not tranny). Leaving just the differential and driveshaft. Taking a driveshaft from the other LS400 (known to be in fine working order) and installed. No more vibration. Course of action- 1 Buy a new driveshaft. or 2 Find a driveshaft shop to balance your existing one use a high speed DYNAMIC method and a quality guarantee. I emphasize that because, like our wheels, the rotational forces in the driveshaft have just as much negative effect as bad wheels. My remanufactured one was supposed to be high speed DYNAMIC balanced but was not. My mechanic demanded only a new part be used at this point. I am working out a refund with the driveshaft supplier. Points of interest- The remanufactured shaft had only 1 weight on one base of the two shafts. The OEM on had tiny and large weights all over both. (little rectangular pieces of metal tack welded on). The shaft alignment was spot on for both. The root cause is unknown. (How do they come unbalanced?)

I have a tach with the same issue but the needle fully illuminate. It just sits there till as occassion occurs where I speed up abruptly. It will then move only slightly from below 0 rmp. Maybe I could spray some viagra in the to help get it up higher. : ) Post something if you find out any further information.

Front x2 ( Engine...yes they are the same) Rear X1 (Transmission mount if you need it) One may affect the other. If the main (Front) mounts are blown, I would replace all three.

My info is from a 92 manual. I am suprised it is that different. Oh well.

I will be sure to mention you at any rate. I love to mess with management sometimes. : ) Sewell Lexus around here is exemplary in every facet except parts prices. I got my Service List from them initially. They are a top notch alternative for factory service. JPI and Davenport Auto are excellent independent mechanics and are more inclined to cultivate custiomer relationships. It is more about geography for me because both are wonderful (one is closer than the other).

PARKING BRAKE 1) Count clicks while pulling parking brake lever completely up. If 5-8 clicks are not counted, parking brake requires adjustment. 2) Raise and support vehicle. Remove rear wheels. Remove adjuster hole plug from rear hub. Turn adjuster (expanding parking brake shoes) until rotor binds. Turn adjuster back approximately 8 notches (until disc turns freely). 3) Install adjuster hole plug. Install rear wheels, and lower vehicle. On ES300 model, remove console box. On all other models, remove cup holder. On all models, loosen parking brake lock nut, and turn adjusting nut until parking brake pull lever travel is correct. Tighten lock nut, and install console box (ES300) or cup holder except ES300).

I use newlexusparts.com for a parts supplier. This web site is also known as Park Place Lexus. I happen on occasion to pick-up the parts instead of having them shipped. On those occassions, I have had nothing but the best service and courtesy. I will on my next occasion as for another print - out for my vehicle and see what kind of situation happens. If I get a unfavorable response, I will insist on the print-out from the next in the chain of command there. I will mention your instance as well and direct him or her to to locate you on the forum for a chance to rectify your situation. my2cents

90LS400Lexus, I also share your grief with the ride. A few questions... Did you ever get that tranny flushed? What kind of tires do have? Does your notice specifically shake all over but is heard (low frequency) from the rear of the car? Have you done something that I have not? ( see prior post) such as bearings, axles, torque converter? While there at the Lexus dealer did you ask them to look into your problem? I have sunk a considerable amount of time and money in this car but am still looking at a good payback if the engine and tranny stay sound for about 2 years. pachocco1

That document is a gold mine. Notice the two indentations. ( north - south ) One definitely has play and might be installed incorrectly or is faulty. Also, another point of interest. I devised a litmus test of sorts for this situation. It calls for a 6 by 2 by 1/2 inch piece of soft wood. (measurements do not have to be exact) With the car raised enough to access the differential area, Lodge the wood (sandwich style) between the sub frame and the differential. It should reduce any play in the whole driveline to about nothing. Take a quick test drive. Hit the appropriate speed range where noise/vibration is present. In my case, it took it out almost completely. My long-term concern here is whether this is the root cause for the problem. I do think several other components contribute to this problem. (Tires, wheel, bushings wear) Thank you so much 99lsguy!!!! I will post any results from this.

I have followed the mount path. (tranny and engine) It lead me to the tires. Replaced. which lead to the wheels. straightened. 2 were bent. Which lead me to the differential. Replaced. ...knucklebushings... ...driveshaft... ...differential mounts(3)... ...rear sub-assembly mounts... So I am running out of options here. Points of interest. Temperature sensitive also! On a rack, the vibration seems to come from the diff. I have put a little peice of wood between the diff and the car frame. it reduce the vibration significantly. There is one side mounted diff bushing and two vertical mounted bushing holding the diff. You can see them from behind the car. I had these replaced recently and it also reduced the overall vibration. But it is still there none the less. When examining the left vert. bushing, I notice that it has a slightly different form to it. Two 1/2 inch indentions in it appear at opposite sides. The other side appears to be a solid rubber mount. With a long screwdriver, I pried at the center bolts of both mounts. The right solid one did not move much at all with a good degree of force. The left one however, moves very easily, but only in the direction of the indentations (pressed in at north -south). There are numbers on the side of the mounts. It starts with a 6 - 0 - 1 - 2 covering about 1/4 of the bushings circumference. My question here is there a top or bottom (and thereby installed incorrectly)? is this left mount deffective ( indentation are not supposed to be there)? could somebody check there car to verify this? BTW, Damn I am sick of this also!!

Not yet anyhow!?!

I feel your vibration woes!!!!!! I have balanced my new tires(3x), fixed my slightly bent rim, replaced worn rear carrier bushings, replaced rear axle boots, replaced the rear differential, Replaced the rear differential mounts (this actually helped alot). The only thing left, that is old, is the drive shaft and the cv joints. Some person on this board once mentioned that an out of balance drive shaft was the root cause of a vibration. I think this is my next part to look at. First. I am going to see if can be balanced. $100? A rebuilt one about ~$350(new u-joints and center bearing etc,) A brand new one ~$700. I will let you know what happens.

Main Entry: drone Function: verb Inflected Form(s): droned; dron•ing intransitive senses 1 a : to make a sustained deep murmuring, humming, or buzzing sound b : to talk in a persistently dull or monotonous tone 2 : to pass, proceed, or act in a dull, drowsy, or indifferent manner I shout this out to my wife on the hwy to persuade her to let me repair the car. dddrrrrrrrrooooooooooooooooooooooooooooooonnnnnnnnnnnnnnnnnnnne... It is a not so common malady called, coincidentally, " the drone" . I have the same problem on a 91LS. TSB reference It is applicable to all cars 96 and before. ( It is misleading on the web site ) Some cars do it and some do not. The repair is extensive being at least $1300 in parts and labor. I has my car on a lift and heard the noise starting around 40 ( very low frequency) and especially around 60-70 ( drone ) then fading out to road and wind noise after that. Initially, I had the differential replaced to discover that it was not the problem. What happens is that the noise emanates from the differential area. It is a problem with vibration. The rear shafts being are out of phase or harmony. The differential vibrates/hums to the point of wear out the differential mounts. This makes the matter even worse/louder!! My independent Lexus mechanic told me that it is not a safety issue but more of a sanity issue. Can you withstand it? It bugs the hell of me.

Can you reproduce the noise while not driving? Push vigorously up and down on the front end of the car. Have a buddy put a keen ear in the location of the sound if there is any. If the creak is toward the front of the wheel, then I would lubricate the sway bar (stabilizer bar) bushings. If problem goes away, replace the bushings. They are cheap and add a good amount of firmness to the overall steering feel. The bushings from a visual inspection will look ok, but the elasticity of the bushing may be shot. I had this problem before and replaced everthing like jzz30. My front end is now very nice. Now on to the rear!

I would get a new leather drivers seat. My !Removed! hurts.

http://www.clublexus.com/index.php/article/view/2068/1/115/

I found my solution after many replaced items(lower ball joints & upper control arms) . The sway bar (stabilizer bar) bushings were the culprit. They looked great but with the car elevated, a tug and pull at the bar revealed a clunk. The unhinging were deflecting off the bar causing the sound. Others have mentioned that spraying some lubricant on the bushing reduces the problem. I found that it only mildly reduced it in my case. After replacement, I am certain that the front end now rides as new. Good luck!

Here is a guess...a bad solenoid? there are four or so, each with a distinct function during shifting. again just a guess. here is a link with some tsb's. see if you are in it. TSB link

The caps will have the numbers already on them to designate what wires are which. As to which cylinder each one goes to, you should just make a quick note of the locations on a piece of paper before starting the install. All the wires are numbered as well. Not too hard to figure out once looking at the whole picture (wires, caps, cylinder locations). The only trouble spot I had was removing the timing belt covers. They were kinda tricky for me because I did want to remove the accessory belt or radiator hoses. Wound up moving the hoses anyway.

I will ask next time I am there.

I had the boots done. The differential and knuckle bushings replaced. All of the above were not the direct problem. I spoke to a Lexus mechanic today and he cited that some older LS400's exhibit this "drone". I say drone because it was the term used in the mechanics service bulletin. It states that the low-pitched noise that emanates during highway speeds from the rear of the vehicle. Because of the low frequency and location, it is often hard to pinpoint where the noise stems from. I listened to the noise the first time with a friend and it appeared to come from the differential. Well we were close. The drive systems in some LS’s have a harmonic that develops over time. The only way to eliminate it is to replace the differential bushings (requires being pressed out) and the sub-assembly bushings. The whole operation is labor intensive to take at least 8 hours. The noise, if it is the case, poses now safety concerns but is essentially an annoyance. I posed a question to him (about the main source of the noise being from the differential bushings) if we could only replace those. He stated that it is possible that it would to some degree but he could not say. A quote for labor and parts at $450 was given just for the diff bushings and at least double that for the whole thing.

For $100 a shop took my rim and used some sort of hydraulic machine to repair it. The result was excellent. A serious flat spot is now completely remedied.

I stand corrected. The differential was not the direct problem. I spoke to a Lexus mechanic today and he cited that some older LS400's exhibit this "drone". I say drone because it was the term used in the mechanics service bulletin. It states that the low-pitched noise that emanates during highway speeds from the rear of the vehicle. Because of the low frequency and location, it is often hard to pinpoint where the noise stems from. I listened to the noise the first time with a friend and it appeared to come from the differential. Well we were close. The drive systems in some LS’s have a harmonic that develops over time. The only way to eliminate it is to replace the differential bushings (requires being pressed out) and the sub-assembly bushings. The whole operation is labor intensive to take at least 8 hours. The noise, if it is the case, poses now safety concerns but is essentially an annoyance. I posed a question to him (about the main source of the noise being from the differential bushings) if we could only replace those. He stated that it is possible that it would to some degree but he could not say. A quote for labor and parts at $450 was given just for the diff bushings and at least double that for the whole thing.

My 91 LS 400 does the same exact thing. I have replaced the lower ball joints, upper control arm and ball joints in effort to remedy the problem. (Didn’t think it was the steering itself originally) The suspension is new as well. (No more air ride) With the engine off and car in park, If I very rapidly turn the steering wheel left and right I can duplicate the sound as it does when I hit a rough road. After evaluating the steering column, I decided to tighten up the U joint that connects the column to the pinion gear. Seemed in good condition. While tightening the u-joint I notice that the rack had a salvage sticker on it. So now, it has become suspect. With similar symptoms, it is down to the following for me: tie rods ( ball joints there ) the rack, the rack damper. One or a combination of these things I believe is/are the culprit. Tomorrow, I am going get a friend to manipulate the steering while I am under the car to pinpoint exactly where the sound is coming from.

wolver1ne516 meant to indicate car-parts.com as the url instead of parts.com . car-parts is a auto salvage directory.