When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I think you may have found a solution to my oxygen sensor issue on my ls600. Dealer ,shops and manual say the engine and transmission have to be removed to replace the sensor.... I have a clear view of the front O2 sensor in your pic. I'd have to make sure the awd/600 is similar enough to gain access but definitely gives me hope it can be done w/o removing the entire Motor🤔🤔
It looks like the 600 has a steel subframe. Aside from that it looks similar. I hope this thread does help you find a better solution. Seems like quite a challenge for a single sensor. I'd be pretty tempted to cut a hole in the floor like someone suggested on your thread LS600
That may or may not be be a rear subframe in the LS600 image. It looks very similar to rear subframe images I've seen.
Yes you are correct, sorry about that. Thank you for pointing out my mistake. The front subframe on a 460 also fits the 600, they are interchangeable. At least according to a few ebay listings
I did my engine mounts, Front sway bar bushings, and front end links 4+ weeks ago. I did not remove the engine, or remove the steering shaft from the rack and pinion. Started about 9:30ish AM and finished by 4 PM same day, including breaks and stopping for an hour or more to clean up, make and eat lunch etc... I did not rush at all and did everything by myself with no assistance from anyone.
My car still had a rattle noise at lower speeds after replacing the control arms and brake pad springs, though those did remove some of the noises I was hearing. I also had a very loud thud when flooring it from low speed, and stopped at stop lights sometimes got a crazy vibration in the car, mostly in the dash and steering wheel, mainly when the engine was cold. This pointed to motor mounts obviously and I knew they would need changed thanks to the valve cover gasket leaks that went uncorrected by previous owners due ot the high pressure fuel pumps being mounted to them. I fixed all of those issues months ago.
I bought aftermarket mounts on ebay. $140 shipped for the pair.
I jacked the front up and put it on stands.
Removed all of the lower covers.
Unbolted the 2 motor mount nuts from the underside of the front cross member.
Unbolted the bolts holding the front of the cross member to the bumper support area. They are small. 2 nuts and bolts going through horizontally on each side. A lil tricky to see if you do not know they are there.
Put a transmission scissor jack under the oil pan, and a piece of a 4x4 on top of the jack.
I removed the end links.
I removed the sway bar.
I removed the brackets the sway bar bolts too.
I removed the bolts holding the rack and pinion to the cross member and unplugged the electrical connectors. I did NOT remove the bolt holding it to the steering shaft.
I jacked the engine up as high as it would go without damaging the oil pan.
I removed the 4 large bolts holding the sub frame to the car, and let it drop as far as possible.
I started on the driver side as that is the usual bad mount on rwd cars. I used a flex head ratchet wrench and removed the 10mm bolts holding the metal heat shield to the exhaust manifold.
I used a combination of ratchets, 14mm sockets, ratchet wrenches and swivels etc.. to remove the 6 bolts holding the motor mount bracket to the block
Once unbolted, I turned it so that the top nut for the motor mount holding it to the bracket was facing the rear of the car so I could unbolt it with my 1/2in ratchet.
I pulled the motor mount bracket out.
I then had to "force" the motor mount between the steering shaft and the block. This is why the rack was unbolted, so that it could be pushed to the driver side for max clearance, and would not throw the steering wheel alignment off.
The mount was shot, as I figured, and the source of the remaining rattle I had, and the "Thunk" under hard acceleration. It looks fine when looking at the car on the lift, but the stud coming out of the top moves freely up and down and all around, while the fluid inside of the mount has splashed/poured out.
I slid the new mount in between the block and steering shaft. I had to force it a bit, but not enough to worry about damaging anything.
I slid the bracket in and arranged it so the stud was threw it, with the nut started and facing the rear of the car so I could tighten the nut.
I put the bracket back in place and reinstalled all of the bolts.
I put the heat shield back on.
I moved to the passenger side and unbolted the heat shield, but it would not slid out like the drivers side did, but would move out of the way to allow better access to the motor mount bracket bolts.
Used the same tools in similar methods to remove the six 14mm bolts holding he bracket to the block.
Rotated it so the nut for the top of the mount was facing the rear of the car so I could remove it with a 1/2in ratchet.
Pulled the mount and bracket out. This mount was not as bad. it moved around all over just shaking he mount, so was nearly ripped apart itself.
I installed the new mount and bracket into he location and rotated so the top nut was to the rear so I could tighten it.
I bolted the bracket back to the block.
I bolted the heat shield back to the exhaust manifold.
I put another jack under the cross member and jacked it up into place. I started the 4 bolts, and moved it to make sure the washers on the bolts fit in the same exact spot as before and tightened them. This took some moving back and forth since I was on my back under the car and not on a lift. Removed the jack I used to lift it.
I put the 4 nuts bolts on the very front of the cross member.
I reinstalled the rack and pinion and reconnected the electrical connectors.
I installed the sway bar mounting brackets.
I installed the front sway bar with new Poly bushings
I installed the new grease-able end links that I greased before installing.
Lowered the jack holding the engine slowly and made sure the studs are in the cross member and reinstalled the nuts.
Reinstalled all of the lower covers.
Jacked the car up and removed the jack stands and dropped it back to the ground.
I now have no more rattles at low speeds, and there is no more vibrations at all when stopped at traffic lights, even when cold. I will try to post pics or vids of the "bad" mounts to show that they look 100% perfect until they are removed. No cracks in the outer portions at all.
Where did you purchase your control arm bushings from? And if you don't mind sharing, what did you pay for them and what's your opinion of them thus far? Getting ready to do the same and replace the four old bags (air suspension) with coilovers and looking for a bushing that might provide a softer ride. Thanks
Nice work William! You beat my time lol. Sounds like you left the subframe still attached, hanging from the rear? I'm surprised you fit the drivers side out that way. This should help the other diy guys without a helping hand.
Spartan8 I used a set of bushings from ebay $55 or so. They were all made in Taiwan according to their bag. I have about 5000 miles on them, no issues so far.
On another car I installed a set of bushings they were $40 or so. They were also listed on ebay but the merchant was local. These bushings before installing felt like the rubber was a lot softer. I didn't drive this car enough to say if there was a road feel difference. If I had to guess these will probably last a bit longer simply because the rubber is softer and maybe less prone to cracking. Here is a link to them. https://www.ebay.com/itm/New-Control...IAAOSwUoxaoh7z
miket000 I just unbolted it so that it would drop down and hang from the tie rods and controls arms to give added clearance. I had to make the mount push through between the block and steering shaft, but I didnt have to use a crazy amount of force. I wasnt trying to race. If I ever do it again, itll go a bit faster as I now know exactly what needs to be removed. I tried to remove it without dropping the sub frame, but my hands and arms are just too big and not enough clearance to pull the mount out.
I figure with my summarized how to, it should help people gte it done a lot faster. Still takes some figuring on angles to get those motor mount bracket bolts out on each side though.
As an owner of a LS460 with a sheared front subframe mount, this will be very helpful in the coming months when I got to replace it. Thank you very much for the writeup.
The subframe swap is done, thank you again miket for the write up, some helpful tips for reinstalling the subframe is to file/ chamfer the edges of the crash bar and subframe so that the parts slide in easier, it makes this a totally viable solo op.
The subframe swap is done, thank you again miket for the write up, some helpful tips for reinstalling the subframe is to file/ chamfer the edges of the crash bar and subframe so that the parts slide in easier, it makes this a totally viable solo op.
Did you change those engine mounts while you had the subframe off. How did the control arm mounting bracket get sheared off the subframe? I just replaced both mounts and took williams advice and just lowered the subframe. This job is very doable if anyone is needs new mounts. I'll upload some more pics so ppl can look at things from different angles.
As an owner of a LS460 with a sheared front subframe mount, this will be very helpful in the coming months when I got to replace it. Thank you very much for the writeup.
Originally Posted by sha4000
Did you change those engine mounts while you had the subframe off. How did the control arm mounting bracket get sheared off the subframe? I just replaced both mounts and took williams advice and just lowered the subframe. This job is very doable if anyone is needs new mounts. I'll upload some more pics so ppl can look at things from different angles.
My vehicle is only at 100,000kms and is a salvage therefore I replaced no motor mounts and only replaced the subframe. I also found out that the entire right knuckle is bent after the accident and need a new one, possibly more control arms. I am also attempting a 2007 to 2013 facelift when rebuilding.
If the force was strong enough to shear off piece of the subframe then everything else on that side of the car is suspect IMO. Junkyard knuckle with new hub should not cost that much.
Thanks to OP and the information in this thread I feel well informed and I will be starting my engine and transmission mount replacements later today or tomorrow. Getting it all set up and ready to go.
03-01-20, 08:19 AM
