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Rear engine mount on 2007 RX400h
Thread Starter
Driver
Joined: Nov 2016
Posts: 63
Likes: 12
From: RI
Rear engine mount on 2007 RX400h
All engine mounts on the RX are worn out and need to be replaced. I’m good to replace the front mounts but am unsure what the best approach is to replace the rear one. It certainly looks like a bear of a job that might not be feasible for a DIY with no possibility to raise the car behind what jack stands can do.
Any tips and tricks from anyone who might have experience replacing the rear engine mount is appreciated.
Thanks in advance,
Any tips and tricks from anyone who might have experience replacing the rear engine mount is appreciated.
Thanks in advance,
Advanced
Joined: May 2016
Posts: 557
Likes: 53
From: Ontario
There are a lot of talented people on this site, I'm sure someone will come through with help. If all else fails, you might want to try this:
https://redirect.viglink.com/?format...nfo.toyota.com
there is also a european site that has full manuals.Do a search and you should be able to find it.
https://redirect.viglink.com/?format...nfo.toyota.com
there is also a european site that has full manuals.Do a search and you should be able to find it.
Racer
Joined: Mar 2011
Posts: 1,817
Likes: 229
From: wa
I had all mounts replaced on my 2012 Highlander hybrid 3.5L. But that's 2012. So I am not sure how much different is your engine, as Highlander hybrid 3.5 L engine is identical to RX400H one... Likely not much of help, but I had no major issues doing so. Worst one was driver side mount. Rear one was easy as I simply dismantled entire mount bracket off the engine.. Install required jacking engine up or down with hydraulic jack and a 2x4 piece placed between jack and engine. That was a "lower torque mount". There is upper torque mount, aka dog bone. That one was hard to get to because of some hybrid component blocking it, but I did it. There was no rear mounts directly at the power train center. R engine mount, lower torque mount that was accessed via R wheel removal, front engine mount, L engine mount, dog bone at the top.
Ramps will be required for you. Or, good jackstands to secure car on. Keep hood up, as you will end with jacking engine up and down. Engine moves quite a bit on mounts as is. Worse case, undo lower mount nuts/bolts, so engine goes up higher. I had it up so much that it was stopped by cowl to remove L engine mount. But the lower torque mount was the easiest to replace. If that's the same one you talking about. It's about in front of passenger feet. Sits on some L shaped bracket and I simply unbolted it off the engine. Was not hard at all.
Ramps will be required for you. Or, good jackstands to secure car on. Keep hood up, as you will end with jacking engine up and down. Engine moves quite a bit on mounts as is. Worse case, undo lower mount nuts/bolts, so engine goes up higher. I had it up so much that it was stopped by cowl to remove L engine mount. But the lower torque mount was the easiest to replace. If that's the same one you talking about. It's about in front of passenger feet. Sits on some L shaped bracket and I simply unbolted it off the engine. Was not hard at all.
Thread Starter
Driver
Joined: Nov 2016
Posts: 63
Likes: 12
From: RI
Interesting. Good information, ukrkoz. Especially the point that ramps will do (I figured the car would be too tilted) and the amount of upper mobility the engine has.
I’ll take pictures of the mounts tomorrow and will post them (raining here now).
I’ll take pictures of the mounts tomorrow and will post them (raining here now).
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Racer
Joined: Mar 2011
Posts: 1,817
Likes: 229
From: wa
Well, ramps if you are not removing wheel. Jackstands if you do. If it's the same mount, you will be way better off having wheel removed and then it's right there. About arm length reach in. So some extensions may be required, but it was very easy to remove. Actually, harder to reinstall, than remove, as two engine bolts didn't want to match, so I had to play with raising engine or lowering it a bit. It's no big deal really. Worst one was driver side mount and dog bone.
Yeah, engine moves quite a bit. All of my mounts were in various stages of deterioration at 90+ K miles. That lower torque mount was the worst one as it takes a lot of kick from torquey engine. When you will pull it out, you will see, how tiny it is for the job done.
Yeah, engine moves quite a bit. All of my mounts were in various stages of deterioration at 90+ K miles. That lower torque mount was the worst one as it takes a lot of kick from torquey engine. When you will pull it out, you will see, how tiny it is for the job done.
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Thread Starter
Driver
Joined: Nov 2016
Posts: 63
Likes: 12
From: RI
I’m not really sure what the rear mount looks like on my vehicle. I wasn’t able to find time today as I was working on my IS350 - seized rear caliper piston. Seems I have all sorts of car issues these days 
.
I’ll report back tomorrow.
.I’ll report back tomorrow.
Racer
Joined: Mar 2011
Posts: 1,817
Likes: 229
From: wa
So I have a question. How did you determine this:
It certainly looks like a bear of a job that might not be feasible for a DIY
without actually looking at the mount?
And you say - ALL mounts.. Trying to remember, what was the problem with the driver side one... I remember, I had to remove some extra piece that was blocking it from the top... and bolts didn't want to come out of the sub frame until I jacked engine all the way into the cowl then used pry bar to pop mount bolts out... that was a bear indeed. Front one was simple, only hard to get to as you have to use 3 extensions joined together to get to the top nut between engine and radiator. Just very awkward....
It certainly looks like a bear of a job that might not be feasible for a DIY
without actually looking at the mount?
And you say - ALL mounts.. Trying to remember, what was the problem with the driver side one... I remember, I had to remove some extra piece that was blocking it from the top... and bolts didn't want to come out of the sub frame until I jacked engine all the way into the cowl then used pry bar to pop mount bolts out... that was a bear indeed. Front one was simple, only hard to get to as you have to use 3 extensions joined together to get to the top nut between engine and radiator. Just very awkward....
Thread Starter
Driver
Joined: Nov 2016
Posts: 63
Likes: 12
From: RI
The backstory: The steering wheel started vibrating a few months ago when accelerating to merge in highway traffic. Thought it was a warped tire or rim. Both checked out ok.
Thrn, 3 weeks ago I had had my son place the car in gear while I observed the engine movement: it rotated about 2-3 inches, indicative of possibly a bad engine mount. I crawled under the vehicle to see if I could identify one or more bad mounts but wasn’t able to, so I took it to a Lexus dealer for a diagnosis. I wanted to confirm my suspicions before doing any work seeing it would be a bear of a job.
The dealer quoted me $1600 to replace ALL mounts (super expensive for $150 worth of parts). I don’t think all mounts are bad, and didn’t question their assessment, but figured I’d replace them all seeing I’d be at it (doesn’t make too much sense in my mind to pay the dealer to do $1600 worth of repairs on a car valued at only $3000 or so - car has 206600 miles).
So, that’s the backstory. Tomorrow I’ll poke around based on your feedback to see what’s involved to replace the rear mount (incidentally, the rubber insert on the top-mounted dog bone shows signs of wear so I know, at a minimum, it needs to be replaced).
Thrn, 3 weeks ago I had had my son place the car in gear while I observed the engine movement: it rotated about 2-3 inches, indicative of possibly a bad engine mount. I crawled under the vehicle to see if I could identify one or more bad mounts but wasn’t able to, so I took it to a Lexus dealer for a diagnosis. I wanted to confirm my suspicions before doing any work seeing it would be a bear of a job.
The dealer quoted me $1600 to replace ALL mounts (super expensive for $150 worth of parts). I don’t think all mounts are bad, and didn’t question their assessment, but figured I’d replace them all seeing I’d be at it (doesn’t make too much sense in my mind to pay the dealer to do $1600 worth of repairs on a car valued at only $3000 or so - car has 206600 miles).
So, that’s the backstory. Tomorrow I’ll poke around based on your feedback to see what’s involved to replace the rear mount (incidentally, the rubber insert on the top-mounted dog bone shows signs of wear so I know, at a minimum, it needs to be replaced).
Racer
Joined: Mar 2011
Posts: 1,817
Likes: 229
From: wa
OK, now I get it. 99% of the time, excessive upper engine end movement is dog bone. That's the one that controls back/for engine upper end thrust. And for what it is, they should have had 2 of them, one on each engine side. It is a VERY torquey engine. Clunks going over potholes and bumps is lower mounts. Specifically, the front one. That "rear" engine mount is simply torque absorber. It does not even suspend much.
Here's food for thought. Vibrations during acceleration is, normally, NOT related to engine mounts. It's axles. You got to check axles out. Get vise grip of suitable size. Lock it on axle shaft next to outer hub and secure handle against the control arm. Now move the wheel, holding vise grip in place. If hub moves, you have bad CV joint. Then, secure vise grip on transmission side of shaft. Grab vise grip handle and move it. If it rotates axle up down without wheel spinning - you have inner joint issue. That is actually the one that will give vibration. Outer clicks in turns.
Back to the dog bone. It's not easy, as it is covered by I forgot what. One of the hybrid components that I'd rather not mess with. I replaced it without removing none of that components. Was not easy. Hold on... the firewall side center dog bone bolt - when undone, it hits brake actuator, I beleieve, and can't be slid out. So I had to jack engine up to bypass it. It's a LONG bolt. I think, I had to undo mounts bolts to allow full up engine movement.. Replaced it with MOOG dog bone.
Here's food for thought. Vibrations during acceleration is, normally, NOT related to engine mounts. It's axles. You got to check axles out. Get vise grip of suitable size. Lock it on axle shaft next to outer hub and secure handle against the control arm. Now move the wheel, holding vise grip in place. If hub moves, you have bad CV joint. Then, secure vise grip on transmission side of shaft. Grab vise grip handle and move it. If it rotates axle up down without wheel spinning - you have inner joint issue. That is actually the one that will give vibration. Outer clicks in turns.
Back to the dog bone. It's not easy, as it is covered by I forgot what. One of the hybrid components that I'd rather not mess with. I replaced it without removing none of that components. Was not easy. Hold on... the firewall side center dog bone bolt - when undone, it hits brake actuator, I beleieve, and can't be slid out. So I had to jack engine up to bypass it. It's a LONG bolt. I think, I had to undo mounts bolts to allow full up engine movement.. Replaced it with MOOG dog bone.
Thread Starter
Driver
Joined: Nov 2016
Posts: 63
Likes: 12
From: RI
This is getting interesting. Sorry for the essay but you’re giving me a bunch of ideas.
A little more backstory:
Last winter of 2017, I was removing replacing front wheel bearings on both wheels. At one point, I pulled the outer drive shaft on the passenger side too much causing the CV joint to “dislocate.” I managed to put it back with no issue (but did not undo the boot). It seemed tight and had no play. Finished the job, took it for a test drive. All was good. Then, sometime in the summer of 2017, I began to hear a ‘clicking’ sound but only when the brakes were applied and ONlY when the car was in gear (no clicking when applying brakes while coasting in neutral). Brakes are good. The strange thing is that the clicking sound appears even by gently tapping the brakes; doesn’t need brakes to be applied fully.
Putting all this together and rationalizing all the observations, I concluded a bad engine mount. Now, to be clear to myself, I checked the drive shafts by applying upward and downward force with my hands ONLY. I wasn’t familiar with your vice grip technique. That’s a clever method. I’ll do it.
Now, I know that U-joints on the driveshaft of a rear wheel drive car will click if badly worn out when it’s spinning. I assume I should hear the clicking sound on a bad CV joint all the time if it’s worn out, not only when I apply the brake. That’s why I assume a bad engine mount since the engine will shift due to inertia when the brakes are applied even slightly. Engine shifts so transmission shifts transferring the shift to the drive shaft causing it to transfer to the steering wheel through the tie rods. Makes sense from a physical perspective but perhaps I’m overthinking it and putting too much faith in the dealer’s honesty ...
So, my next steps is to do a couple of checks on the engine mounts and then perform the vice grip to drive shaft test. It’ll take me a couple of days.
A little more backstory:
Last winter of 2017, I was removing replacing front wheel bearings on both wheels. At one point, I pulled the outer drive shaft on the passenger side too much causing the CV joint to “dislocate.” I managed to put it back with no issue (but did not undo the boot). It seemed tight and had no play. Finished the job, took it for a test drive. All was good. Then, sometime in the summer of 2017, I began to hear a ‘clicking’ sound but only when the brakes were applied and ONlY when the car was in gear (no clicking when applying brakes while coasting in neutral). Brakes are good. The strange thing is that the clicking sound appears even by gently tapping the brakes; doesn’t need brakes to be applied fully.
Putting all this together and rationalizing all the observations, I concluded a bad engine mount. Now, to be clear to myself, I checked the drive shafts by applying upward and downward force with my hands ONLY. I wasn’t familiar with your vice grip technique. That’s a clever method. I’ll do it.
Now, I know that U-joints on the driveshaft of a rear wheel drive car will click if badly worn out when it’s spinning. I assume I should hear the clicking sound on a bad CV joint all the time if it’s worn out, not only when I apply the brake. That’s why I assume a bad engine mount since the engine will shift due to inertia when the brakes are applied even slightly. Engine shifts so transmission shifts transferring the shift to the drive shaft causing it to transfer to the steering wheel through the tie rods. Makes sense from a physical perspective but perhaps I’m overthinking it and putting too much faith in the dealer’s honesty ...
So, my next steps is to do a couple of checks on the engine mounts and then perform the vice grip to drive shaft test. It’ll take me a couple of days.