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How to replace upper control arms, detailed tutorial
I see many people unsure if they can pull this off, so I decided to go into every single detail of how to do it. I can guarantee you will be able to do it yourself, EVEN IF IT'S YOUR FIRST TIME WORKING ON YOUR CAR, after reading this.
So, first of all, buy new upper control arms. For 1st gen, lexus part numbers are 48610-50020 and 48630-50020. If one is gone bad, the other one will soon, so you may as well do them both at the same time, besides, you will need to do wheel alignment, so better replace them both.
General consensus seems to be that moog is not as good as it used to be and you can't even go by their serial numbers (same first letter like "k" does not necessarily mean it is made in the US or Japan - could be anywhere, including China), and also that Dorman is pretty good. I remember the first time I did this job, dorman UCAs were just as beefy as OEM. They held for about 5-6 yrs, of constant city driving over terrible potholes, so that's not too bad. With them you will get one new castle nut and one new cotter pin. I prefer Dorman castle nut - it is stronger, while OEM one is made of brass or something - I broke it easily (my fault, but still, it was as soft as butter).
If you buy Dorman UCAs, they come with a new castle nut and a nice stiff cotter pin. If you don't have those, you can reuse the nut but not the cotter pin - head off to your local auto store and buy a package of cotter pins. It is better to use good quality ones, because I have seen cotter pins rust and fall off.
Anyway, here's the tutorial:
1. Brief explanation: if you look above your front wheels you should see something like this:
That black new part with the blue line and rubber boot below is an upper ball joint on LS400 (looks pretty much the same on both 1st and 2nd gen, but they are not interchangeable). On those two models, upper ball joint is integral part of the upper control arm, so if your ball joints are loose, you need to replace the entire control arm (the thing that has the shape of the big wishbone), with ball joint in it. (NOTE: Some guys have managed to replace the ball joint only. Obviously this is cheaper, and requires a bit of work, strong press and so on. So, yes, its at least possible but hardly anyone does it)
If you hear faint squealing noise as you go over small bumps at low speed, or even at higher speed, and possible "clunk" when turning into your driveway, or going over bumps, that's your ball joints getting loose and should be changed. Also, your steering will be less precise. If you don't change them in time, you risk losing your wheel, and with that your life or whoever is driving the car.
2. Most tutorials say you need to completely remove struts. You only do if you want to use the torque wrench, which is a good idea, but considering those two bolts need to be tightened really hard, most people just tighten the heck out of them with a box wrench. If you decide you don't want to remove the struts, you may have to loosen the nuts holding the strut in place, and jiggle it a little to pull out the two bolts holding the upper ball joint in place, because the spring will be in its way, but that's about as far as you have to go. If you want, and if you want to go by the book, you can remove them, it will give you more space to work which you need if you want to use torque wrench. Since torque is quite high, I just made sure I torqued it as much as I could, which I estimate to be at least 120ft lbs.
Here is a picture of both bolts and how they are just between the springs, or they may touch it a little on their way out: Upload
3. Before you raise the car, you need to know what is the distance from the top of your wheel well to the center of the wheel. Once you raise it, the wheel is up in the air, hanging off the suspension, and obviously much lower - about 2 inches lower than when resting on the wheel. I measured and raised it was 18in from the top of the wheel well arch, while on the ground it was exactly 16in from the top of the wheel arch to the center of the wheel. My struts are brand new (OEM), so your numbers may be different. Below is the picture of how that's measured, except the car is already raised - you should do it BEFORE you raise the car. You should also loosen wheel nuts before you raise the car, unless you are using power tools.
3.Chock the rear wheels, engage parking brake and raise the car's front end. There is a cross member, between oil pan and AT pan, it is shiny, you can't miss it. You can raise there to jack up the car. Alternatively you can raise each side separately. Your choice. Make sure your jack is not even touching anything else, like those oil pans, otherwise, you'll be crying all the way to the dealership to buy and install a new one. (oil pans are fragile) Use a strong jack because this is one heavy car. I use steel one that can lift 3000lbs. (I used to use a smaller, aluminum one, 2500lbs and it broke after a while. I liked it because it was light, and easy but it didn't hold over time. So a bigger, heavier jack is better!)
4. Put stands on each side of the car, if you don't know how, find it on the net, but generally, if you look under the front part of your front doors, you will see two little notches at the very edge - between them is where you need to put the stands and the lip between those two notches should fit in the U part of the jack stand. Make sure the car is lifted sufficiently so that when you release the jack, the wheels are still off the ground. Make sure the stands are secured properly - shake the car, try to get it to do something stupid. It shouldn't if you did everything right.
5. Take off the wheel, it's the same thing as when you are changing the tire. If you forgot to loosen the nuts before raising the car, you could try this trick:
I used a 21mm combo wrench to stop the wheel from turning - you should put something between the wheel and the wrench so you don't scratch the wheel. but ideally, you should not do this (I actually didn't do it like that, just showing that there is a trick in a pinch...)
6. once your wheel is off, things should look like this:
7. Now, you can start unscrewing the bolts. There are two bolts at the top, and those are the hardest thing to do in the whole job. Those are the bolts above, in the step #2 - left and right one.
8. Use a box wrench to loosen them, like this:
(watch out, your brake lines may be in the way - don't damage them!)
If you need more torque (those two bolts are probably very tight!), you can use this trick (however, theoretically and depending on the quality of your combination wrench, they could snap and break from pressure, or slip, or something and then you end up injured, so obviously - make sure you don't put your face up against it, but move out of the way as much as possible):
9. Once those two bolts are loosened, leave them in there, don't have to take them out right away.
10. Next step: remove the cotter pin as in the image below (I actually had to cut the pin, it was so bent out of shape and impossible to just pull through the hole) and then loosen the castle nut that holds the ball joint. Use a 19 mm deep socket, do NOT use a wrench because you could easily strip it or break it!!! (I stripped one!) On my car there was an "R" pin - those are actually reusable, but cotter pins are not!. If you need help with removing cotter pin: use needle nose pliers, pull it back through the hole. If it refuses, cut it with the cutting part of your pliers - it works like this:
10. Then pull out the cotter pin, and see if you can separate the ball joint from the thing that it is screwed into - the steering knuckle. Sometimes it takes no effort, sometimes it takes quite a bit of it. No need to bang on it - if it doesn't come out easy, then use the pitman puller (using some other model of the puller may not work! I tried one and it was a disaster - too small and always slipping, couldn't do anything with it) This one is perfect (part number Pitman 27022 - should be the same one they rent at Autozone:
11, Take the puller out of the box and place it around the steering knuckle so that its screw is pushing against the screw of the ball joint, while the sides are clamped onto the sides of the steering knuckle, like this (The puller is touching the rubber boot on the UCA, so I was careful not to damage it until I realized - it's garbage anyway ! But, anyway, the puller doesn't need to grab the rubber at all - it should be below it, just like in the picture.
12. Screw in the screw of the puller using your wrench (19mm I think) untl the ball joint pops out of the knuckle.
13. Once it's out, the knuckle is free to fall, so make sure you either place it on some box, or tie it up to the spring using wire, rope or zip tie (I used a zip tie)' like this:
You can also tie it to the spring. (Image above is taken from Lexls.com, hope he doesn't mind). If you don't support the knuckle in some way, it will be held by only the brake line, and that is a dangerous idea. Brake line is not meant ot carry any weight.
14. Finish unscrewing the two bolts at the top of the UCA. If they hit the spring, you have to unscrew the strut assembly too: one of the screws is at the bottom of the shock, I think it was 19 mm, the others are three of them, on the top of the wheel well, when you open the hood. Easy to find, and they are 12mm I believe. The one on the bottom may be hard to unscrew, but there is plenty of space for breaker bar if needed. Those on the top don't need to be torqued too much once you put them back. This step is not that hard, and all you need to do is remove those screws so you can jiggle the strut a little to make it easier to pull out the bolts. If you are lucky, the bolts will fit right in between the spring and you dno't need to do that. On my car, two bolts on the left side fit between the spring (after I raised them a bit, with a jack), so I didn't have to unscrew the strut, but one bolt on the right side hit the spring squarely and was impossible to remove, so I loosened the strut, jiggled it a bit,(it drops from the top), and the bolt came out no prroblem. The bolts are very long, but the more they are out, the more play there is in them, because they are not screwed along their entire length, only their tips have threads. IF you need more info on this, you can find it on LEXLS.com, under suspension - how to remove struts.
15. Now that UCA is not held by anything, take it out. It may be a bit tight up there, but not too hard to remove.
16. Put the new one in. Strangely, on my right side, I could not fit it in - the space was tight. I used a wrench as a leverage to push it in its space. Just play with it until it fits, it should be no big deal.
17. Put the two top bolts back in, but do NOT tighten them yet. Only loose. Put the bottom castle nut on it, and do not tighten that either. (There is another school of thought here; since the two screws go through bushings which sit protected by car's metal on BOTH sides, the tighetning of those two bolts really does not, or should not affect the bushings at all! You can see that when you put in the new UCA, the bushing is relatively loose inside its slot. So, I believe the bolts are really tightened against the car's body, not the bushing. In that case, the whole deal about raising the car to ride height becomes unnecessary, but who knows... my Doorman UCAs came with that warning to raise the car to ride height first. so there.)
18. Now, important part: you have to raise the suspension in order to tighten the UCA bolts in riding position. If you don't do this, you will tighten them when they are too low, which wil then twist the rubber inside the bushings, and destroy it quickly.
This is how I did that (view from the left side of the car, as I was working on the front left UCA); place the jack next to the driver's door. slide it under the lower ball joint, and make sure you don't press it against the bolt at the bottom:
View from the opposite side (from the front of the car so you can see I am not pushing on the bolt):
That's the right wheel, looking at it from the front The jack is next to the driver's door, and you make sure you don't push on the bolt down there, but next to it, on the metal part. Ideally you wan't to use a piece of wood to avoid sharp metal to metal contact.
Pump it up, as far as it will go, and you will see that the entire car will start going up but it will still be about half an inch below ride height. I figured, 16.5in is pretty close to 16, so I tightened it at that point. Use the same box wrench to tighten them as you did to remove those bolts. The proper torque is 83ft lbs (thanks deanshark!).
19. Now the castle nut: the single most important thing here is to not overtorque it. If you do, you will shorten the lifespan of the ball joint, at least, that's what I think. Someone on Lextreme has the correct torque as 80 ft lbs, but I think that's incorrect. The correct number is 48 ft lbs. No need to overtighten it - there is a cotter pin there anyway. In my case, the nut was way above the pin... I guess that's fine, as long as you place the pin so that it cannot fall out. I bent mine around so it is there tight. Mine was also a bit too long, so I cut off the extra bit.
20. If you have removed the struts, put them back in. The proper torque values are: 43ft lbs for the top three nuts and 105ft lbs for the bottom bolt.
20. Now you can lower the jack, put the wheel back in place, and you know the rest. Tip: to avoid struggling with placing the wheel, aim only for the top hole of the wheel. If you get that one in, the rest will slide in.
21. Tigthen the wheel nuts, but don't overdo it - around 95 ft lbs is enough. If you overtighten using power tools, you may not be able to remove it if you have a flat tire and only OEM tools in the trunk!
Time it takes is about one hour per side, at leisurely pace.
Glad you like it! It was high time someone did this without skipping any details, and I figured it was my turn
ps. I just corrected few minor errors and added one more picture
Just want to point out a few things on this. It's alot better to do it correctly and remove the struts.
1st, If you don't own a torque wrench then go buy one, or rent one from Autozone. You need it.
2nd, You don't need to measure any ride height. You just tighten the 2 bolts to the correct torque, which is 83 ft lb. It is not " most people just tighten the heck out of them with a box wrench." or "Since torque is quite high, I just made sure I torqued it as much as I could, which I estimate to be at least 120ft lbs." Tightening them too much WILL make them wear prematurely. 3rd, Peter, Your ball joint is tightened up way too high. The correct torque on the ball joint is 48 ft lbs. The cotter pin is supposed to be through the grooves on the castle nut, that's why it's not a solid nut. Torque to 48 ft lbs and if the hole doesn't line up through the nut, tighten a little more til it does. The correct torque for the strut is; Bottom bolt--106 ft lbs. Top 3 nuts---43 ft lbs. Not as you put it---"don't need to be torqued too much once you put them back" ALL torque needs to be correct.
To point out a couple things on your car you might want to fix, or at least look at. Looks like you're gonna need outer tierods very soon. The rubber boot is all messed up in that pic. Also your brake dust shield is bent. Make sure it isn't hitting anything, like rubbing on a brake line. I'd hate to hear that you lost your brakes.
...18 ...
Pump it up, as far as it will go, and you will see that the entire car will start going up but it will still be about half an inch below ride height. I figured, 16.5in is pretty close to 16, so I tightened it at that point. Use the same box wrench to tighten them as you did to remove those bolts.
...
Yes, and what I've learned is that measuring the hub-to-fender distance is not actually needed because of this. I just jack the hub until the car barely lifts off the jack stand, and that's pretty close. And like you noticed, jacking further will not change much ... until you lift off the opposite side jack stand too.
The discrepancy is due to the jacking point you chose vs. where the wheel normally sits. If you were to jack a little further outboard, such as at the brake rotor (would need to have someone in the car with their foot on the brakes to make sure the rotor does not rotate), you'd find the jack stand liftoff point exactly matched your previously measured hub-fender distance. And more specifically why - the jack-stand liftoff happens due to the upward force from the jack, while the hub-fender distance reduction happens due to the torque about the inner pivots on the lower control arm. If the lever arm between that pivot axis and your jacking point was the same as the wheel imparts, it would be identical. Since you're inboard by a few inches, you get less torque when you use the same force (jack-stand liftoff).
As you mentioned, it is important to get close to the normal ride geometry before torquing the bushings. In fact they should be allowed to move freely before tightening in the correct geometry. You don't want to pre-load the rubber, as it will cause premature wear.
So summarizing, what I typically do on all my cars is to skip the distance measurement, and when jacking the suspension to achieve the normal geometry, I try to jack at a point near where the center of the wheel is, which is normally near the rotor.
EDIT - I just saw deanshark's post ... what is it about these bushings that does not require geometric alignment before tightening? Do they rotate in sleeves or something? I use the procedure I described pretty much all the time for all suspension bushings unless I'm sure it is not needed.
And also, those bolts can be tricky to get in / out past the coils in the spring, depending on how lucky you are about where a particular coil sits. I've found that either jacking the suspension to move things a little, or using a strut compressor (just needed a little - enough to move the coil up or down enough to provide clearance needed for the bolt to come out).
Denashark, thanks for your input! I will update the above as per your instructions. Can you really confirm that the proper torque is 83ft lbs for the two bolts? I can't remember where, but I read somewhere ti was 120...
The castle nut: that one really surprised me. I mean, I was not tightening it too much, but it kept going and going... and finally when I felt some resistance it was already beyond the holes. I know that the very reason there is a castle nut is so that the pin can fit through the groove, but this one just goes way beyond. I even loosened it again, and unscrewed it and then screwed it in again, and it went beyond, and my torque wrench was set at 48 (give or take 1lb because of the small notches).
The only thing that comes to mind is that my torque wrench may be broken. When I torqued the wheel lugs, i noticed that the wrench part which holds torque started sliding! I mean, it's supposed to stay in place, once you set it at certain torque, and it seemed to work (it's a click type torque wrench this one:
), but the metal handle part which points to torque value got lose and was sliding up and down (its the part with cris-cross grooves). Didn't do that before... I imagine if I push it against the black ring at the bottom that tightens it to specific value, it should be just fine. but maybe not?
As for the torn out tie rod boot - yes I noticed that too, when I took that picture (it's dark in there). Hoping to replace that soon.
As for the brake dust shield - I had to bend it away because I upgraded the brakes to 2nd gen, so the disks are larger and the shield is in the way. Others have done the same, and the car has been this way for few years now, no problems although I'd much rather install OEM 2nd gen shield if I found one and if it wasn't a PITA to install (don't know if it is).
OK, on to changing those specs now.
Thanks!
2nd, You don't need to measure any ride height. You just tighten the 2 bolts to the correct torque, which is 83 ft lb.
Doorman UCAs came with a printed warning, something to this effect:
"Raise the suspension to ride height before installing to avoid premature wear" or something to that effect. I threw away the packaging and that paper, but was surprised to see it there - nice of them. OTOH, don't know if overtightening the two bolts really does damage, as the bushings are sitting in their own slot, protected by metal on both sides. Tightening the bolt does not really press on anything except on the metal slot, not the bushing, so I am not sure that either torque or ride height installation makes any difference (obviously, as long is they are not loose)
Quick question for deanshark and oldskewel and anyoone else who knows: if the torque wrench screwed up while I was putting on the castle nut, could it be that it was overtorqued without me knowing? What if I get the castle nut off again and leave it off for a while - would the rubber inside the ball joint expand back into its original shape if I overtorqued it?
I am really pissed - I'd never imagine that a torque wrench which I used all of I dunno, maybe 50 times if that (I admit, I use a weak Harbor freight electrical wrench that does just about 100ft lbs, when in a rush to put a wheel back on), without using the wrench, so that wrench really didn't see much use, and I NEVER used it as a tool for screwing and unscrewing things, only for torquing).
ps. Still thinking about the stupid torque wrench... I noticed the last time I was putting on the wheel lugs, it took quite a bit of force to put it to proper 93ft lbs (if memory serves) for them. I was thinking - "am I getting weaker?" Could it be that my torque wrench was lying to me for a while and only now that became apparent with this part sliding off???
Just looked around few reviews for Doorman UCA and found out that others had the same problem - properly torqued, it went way above the cotter pin, like mine. Maybe all is good, dunno anymorre..
BTW, I updated the above tutorial with specs give by deanshark.
EDIT - I just saw deanshark's post ... what is it about these bushings that does not require geometric alignment before tightening? Do they rotate in sleeves or something? I use the procedure I described pretty much all the time for all suspension bushings unless I'm sure it is not needed.
Oldskewel, it is even more interesting than that. You can see in my pictures that there is a slot for the two bushings inthe body of the car. Metal on both sides, and one of mine was a bit tight, so I had to use a bit of force to pry it wider (just a hair though - you can't really bend it much at all).
So, now I am wondering: if there is a metal slot, into which the bushing fits quite easily, and then the bolt tightens to the metal that is NOT a part of the bushing, the torque probably makes very little if any difference, including having the ride height while torquing! The bushings should be loose in there, safely tucked away and protected by car's metal on both sides, and then the bolt goes through and holds them in place.
I imagine we could check this out by removing the castle nut, separating the ball joint from the knuckle and try to move the UCA up and down, around the two bolts. If it moves easily, which I believe it should, then, the whole "ride height install" is a waste of time.
What do you guys think?
Denashark, thanks for your input! I will update the above as per your instructions. Can you really confirm that the proper torque is 83ft lbs for the two bolts? I can't remember where, but I read somewhere ti was 120...
06-07-19, 02:32 PM
How to replace upper control arms, detailed tutorial
! But, anyway, the puller doesn't need to grab the rubber at all - it should be below it, just like in the picture.
Thanks for the detailed tutorial.
