Front Lower Control Arm Romoval/Replacement (1 Viewer)

[Patassa]

Don’t have to completely remove torsion bars to pull LCA. Just need to unbolt bracket from LCA and hammer bracket off of torsion bar splines onto arm of bar. Loosen the torsion bar adjustment bolt first, though, to take tension off the the bars and LCA.


That’s not possible, given the rearward LCA bolt’s head is located behind the torsion bar bracket, and the bracket must be installed before putting any weight on the suspension...


Replacing the control arm bushings is only crappy part about this job...they can be a bear to get out, which is why a lot of people just buy new control arms with new bushings already installed. However, I replaced all of mine. Torch, chisel, hammer, and hacksaw were all useful for getting the old ones out. New ones press in without issue. Also, the #2 LCA bushing is in the frame. In can be pressed in and out using a threaded rod, couple of big washers and nuts, and appropriately sized sockets.

Not quite sure what you mean by it not being possible, it worked fine for me. You never want to tighten the lower control arm bolts to spec without the arm being under full load.

I'm struggling here too, how do I torque that LCA bolt but also have the TB bracket installed which appears to block it from me being able to get a wrench on it? Otherwise, I can torque it with the bracket out of the way but that wouldn't be at ride height.

 

[JunkCrzr89]

I'm struggling here too, how do I torque that LCA bolt but also have the TB bracket installed which appears to block it from me being able to get a wrench on it? Otherwise, I can torque it with the bracket out of the way but that wouldn't be at ride height.

Slide open end wrench inside the gap of the TB torque arm from below to hold the LCA bolt head, then put torque wrench and socket on the nut.

That’s what I did. I should probably revise my previous response to @TheForger that you quoted, as I think I misunderstood what he meant (my statement about it not being possible was wrong).

 

[Patassa]

Slide open end wrench inside the gap of the TB torque arm from below to hold the LCA bolt head, then put torque wrench and socket on the nut.

That’s what I did. I should probably revise my previous response to @TheForger that you quoted, as I think I misunderstood what he meant (my statement about it not being possible was wrong).

It's giving me absolute hell tonight. This is a standard issue, harbor freight 24mm, what kind of wrench are you guys using that will fit in the slot?
Right now, I'm at the "blue locktite and impact the s*** out of it" stage of frustration trying to use a huge torque wrench under this vehicle at ride height, and no great way to keep the bolt from turning.

No way that wrench is getting in that slot. What gives? Lol, thanks.

 

[flintknapper]

It's giving me absolute hell tonight. This is a standard issue, harbor freight 24mm, what kind of wrench are you guys using that will fit in the slot?
Right now, I'm at the "blue locktite and impact the s*** out of it" stage of frustration trying to use a huge torque wrench under this vehicle at ride height, and no great way to keep the bolt from turning.

View attachment 2479892

View attachment 2479893

No way that wrench is getting in that slot. What gives? Lol, thanks.

Grind it thinner or do what I did (took two tapered punches and tapped them up against the flats (both sides) of the nut so it couldn't turn. Then use a hammer to tap the punches back and forth to loosen them to remove.

 

[Patassa]

Grind it thinner or do what I did (took two tapered punches and tapped them up against the flats (both sides) of the nut so it couldn't turn. Then use a hammer to tap the punches back and forth to loosen them to remove.

Ah, ok figured I'd have to improvise but wanted to make sure I wasn't missing something first. Thanks.

 

[flintknapper]

Ah, ok figured I'd have to improvise but wanted to make sure I wasn't missing something first. Thanks.

No....you had it pegged. They made it pretty much impossible to get to.

 

[AlpineAccess]

I have done everything but the lower bushings on my 100s front suspension. That being said I have done lowers on a number of Toyotas though, as well as several trucks with torsion bars. On those I marked the ride height position on the arm with a paint pen with the vehicle on the ground.

Once the new lower control arm bushings were in and the arm was on I aligned the marks with my floor jack under the arm so I knew the arm was at ride height.

Then torqued down the bushings and then removed the jack and attached the torsion bar mounts.

Is there a reason this wouldn't work on the 100?

 

[Patassa]

I haven't done everything but the lower bushings on my 100. I have done lowers on a number of Toyotas though, as well as several trucks with torsion bars. On those I marked the ride height position on the arm with a paint pen with the vehicle on the ground.

Once the new lower control arm bushings were in and the arm was on I aligned the marks with my floor jack under the arm so I knew the arm was at ride height.

Then torqued down the bushings and then removed the jack and attached the torsion bar mounts.

Is there a reason this wouldn't work on the 100?

Thought about doing this as an alternative as well

 

[awesomeissquid]

So quick question on this as I am preparing to reinstall my front end. I have been following the FSM and it seems to differ from the procedure discussed here. FSM says to do the following order for reinstalling the LCA (reverse order of removal):

1. Install 3 bolts and 2 nuts in lower suspension arm, Torque to 230 Nm.
2. Connect steering knuckle to lower suspension arm, Torque to 159 Nm and install cotton pin.
3. Connect shock absorber to lower suspension arm, Torque to 135 Nm.
4. Connect stabilizer bar link to lower suspension arm, Torque to 52 Nm.
5. Install front torsion bar spring.
6. Install engine under cover.
7. Install wheel.

In the discussion here it seems most suggest only applying the final torque to the suspension assembly when at operating height. This matches what I believe is common practice. I was hoping to understand why the FSM suggests to not do that and if it would work as described in the FSM?

 

[awesomeissquid]

I wanted to close the loop on this for anyone in the future looking for some information based on what I have found trying to answer my own questions.

All suspension components must be torqued at ride height. The reason for this is two fold.

1. The bushings have teeth that bite into the frame when they are torqued.
2. The rubber in the bushing wants to maintain the un-sprung alignment (i.e. alignment when installed with suspension at ride height). Each bushing can be thought of as a torsion bar that helps maintain the ride.

If the bushings and the suspension components were to be installed either fully extended or compressed, then the bushings would be at an unnatural twisted state at ride height. This would put additional wear on the bushings, hence the reason for needing to install and torque suspension components at ride height.

 

[Patassa]

I wanted to close the loop on this for anyone in the future looking for some information based on what I have found trying to answer my own questions.

All suspension components must be torqued at ride height. The reason for this is two fold.

1. The bushings have teeth that bite into the frame when they are torqued.
2. The rubber in the bushing wants to maintain the un-sprung alignment (i.e. alignment when installed with suspension at ride height). Each bushing can be thought of as a torsion bar that helps maintain the ride.

If the bushings and the suspension components were to be installed either fully extended or compressed, then the bushings would be at an unnatural twisted state at ride height. This would put additional wear on the bushings, hence the reason for needing to install and torque suspension components at ride height.

Can confirm, also the pre load on the bushings causes a really "squirrelly" handling feel, in my case.

 

[lesgarten]

Can confirm, also the pre load on the bushings causes a really "squirrelly" handling feel, in my case.

How did you go about putting it right? Mine is feeling that way as well.

 

[Patassa]

How did you go about putting it right? Mine is feeling that way as well.

Jacked it up, loosened every nut and bolt having to do with control arms/suspension. Then set it back down, re torqued everything at ride height, its a total pita because of clearance issues getting under there and fitting the torque wrench. Many times it was 1 click at a time, miserable but fixed all my issues.

 

[shtbrwn86]

7) I used a floor jack to lift and compress the front AHC shock by lifting the LCA. Bleed any pressure from the shock's corresponding AHC accumulator. This will let the shock fully compress so the LCA will float up and down. Since the TB arm has been disconnected at the rear, you should be able to move the LCA up and down by hand. This is the most important part.

I am getting ready to do this and didn't see anything about bleeding pressures in the accumulators in the FSM. If it's there I missed it. In fact I don't recall anything about the shocks other than unbolting them.

And when you say bleed the pressure from the accumulator... you mean crack open the bleeder valve next to the corresponding globe? Again, don't recall anything in the manual. Is this just a "pro-tip" that's not listed in the manual?

 

[flintknapper]

I am getting ready to do this and didn't see anything about bleeding pressures in the accumulators in the FSM. If it's there I missed it. In fact I don't recall anything about the shocks other than unbolting them.

And when you say bleed the pressure from the accumulator... you mean crack open the bleeder valve next to the corresponding globe? Again, don't recall anything in the manual. Is this just a "pro-tip" that's not listed in the manual?

Just unbolt them.

Bleed off pressure if you have a specific reason to. I didn't.

 

[shtbrwn86]

It would obviously be much easier to do this job with a lift, but since most of us don't have lifts, are you guys putting the wheel back on and crawling under and torquing everything at that point? Man, seems like quite a PITA. I am really intrigued by @AlpineAccess method, especially when it comes to tightening the bolt behind the torsion bar bracket.

 

[shtbrwn86]

@OwnerCS I just slackened the TB's till loose. Undid the nuts. Then tapped the TB Torque arm back towards the shaft till I got clearance to remove the LCA bolts. The Torque arm is still engaged to a bit of the splines.

This may be a stupid question, but should I un-crank the torsion bars when the vehicle is on the ground or should I do it with the front end raised? Does it matter? I was thinking I need to un-crank it pretty much all the way until the adjustment bolt is almost undone and then remove the front bracket?

 

[flintknapper]

This may be a stupid question, but should I un-crank the torsion bars when the vehicle is on the ground or should I do it with the front end raised? Does it matter? I was thinking I need to un-crank it pretty much all the way until the adjustment bolt is almost undone and then remove the front bracket?

I did mine with the vehicle's front end lifted (and frame supported on jack stands). That way it is much easier to turn the adjustment bolt without the weight of the vehicle acting against the Torsion Bar.

 

[shtbrwn86]

Not hard at all. Find the threads on reindexing torsion bars, except you will take it a step further and complete remove them. Jack the truck up. Remove wheel. Pull the lower ball joint. Support axle & UCA with something to prevent them from drooping too low and pulling the axle out of the diff. Undo lower control arm bolts. Replace with new LCA and hand-tighten the bolts. Replace torsion bars and torsion bar bracket on the LCA (I would recommend installing the reinforcement bracket at this time also) by following the steps in the thread I linked above to reindex them. Replace ball joint. Put the truck back on the ground so all the weight is on the 4 tires and tighten the LCA bolts to spec. I would also recommend replacing all the bolts & nuts with new.

I just removed my passenger side front LCA and thought I was being smart and wratchet strapped the hub to the upper control arm. Didn’t really think it through and when I removed the LCA the hub assembly was supported by the UCA/axle.
Any chance I damaged anything? I’ve since strapped it to the frame as well as putting a jack under where the ball joint would go.

How would I know if the axle has been pulled out of the diff? To clarify I am wondering if letting the knuckle/hub rest on the upper control arm with no support underneath would the axle come out of the diff even just a little? But the more I think about it, I doubt that would happen since I still had the tie-rod end connected as well as the knuckle to the UCA. I imagine it would would pretty hard to pull the axle out of the diff with those still connected? Is there anything in the suspension/frame that limits how down the UCA can travel on it's own?

The droop didn’t appear to be too much.. axle appeared to be fairly straight?

 

[JunkCrzr89]

I just removed my passenger side front LCA and thought I was being smart and wratchet strapped the hub to the upper control arm. Didn’t really think it through and when I removed the LCA the hub assembly was supported by the UCA/axle.
Any chance I damaged anything? I’ve since strapped it to the frame as well as putting a jack under where the ball joint would go.

How would I know if the axle has been pulled out of the diff? To clarify I am wondering if letting the knuckle/hub rest on the upper control arm with no support underneath would the axle come out of the diff even just a little? But the more I think about it, I doubt that would happen since I still had the tie-rod end connected as well as the knuckle to the UCA. I imagine it would would pretty hard to pull the axle out of the diff with those still connected? Is there anything in the suspension/frame that limits how down the UCA can travel on it's own?

The droop didn’t appear to be too much.. axle appeared to be fairly straight?

View attachment 2641383

Axle might pull out of the diff some. Generally, you want to pop off the dust cap and remove the c-clip, then slide the hub assembly out and forward. But leaving it attached to the UCA is not problem.