Nissan 370Z Forum - View Single Post - Front Lower control arms bushes removal (z34)

ZPWR · 04-16-2021, 07:57 PM

Alright. Just to update this thread of mine. I managed to DIY one of the front lower control arms. Removal and installation is pretty straight forward. I may write something up in the future about a specific DIY for the Front lower control arm bushes as I can't find any other posts related to this apart from Rusty's SPL control arm bushes thread found in this link:
The Complete SPL Front Suspension

The main reasons for this DIY are maintenance issues related to suspension noise and/or steering issues as well as modifying the bushes to better quality & longer lasting materials instead of the factory hydro-filled bushes that crap out so early. The benefits of doing this is greater stability in forward and backward motions of the car making it more stiff which I guess in a way also improves the handling. And you also won't have to worry about repairing these control arms ever again after this DIY.

Due to the revised and upgraded suspension design of the z34 compared to the z33 (350z), the double wishbone control arms on the front especially the lower control arm on our 370z are a real B$-word to maintain and repair due to the tight spaces and exposed brake fluid and fuel lines on both sides that you have to pay special close attention to not to break or even accidentally "bump" as you remove/install the lower control arms. It's super awkward and requires abit of mechanical skill to work around with the whole front wheel hub assembly. A second pair of hands definitely helps. But not too difficult for the determined few who enjoy DIYs. This is one of the more challenging yet rewarding ones imo. Considering what options you have to remove and refit the bushes which is the part I struggled the most in this DIY as a backyarder.

But a quick write up of what I did to make this possible with aftermarket bushes (like SPL) for all you DIY'ers out there who are thinking of doing this yourself:

- Jack front of car, ensure park brake is on, chock rear wheels for added safety, wheels off, inspect bolted points for lower control arms.

- Bolt points control arm - Ball joint nut, sway bar end link to shock bolt and nut, front impact small bush bolt & nut, rear large bush bolt & nut.

- *MUST* Jack akebono brake assembly preferrably on the disc (helps to have brake pedal temporarily pressed in to prevent disc from rotating) BEFORE removal of control arm. Ensure disc is sitting securely. This prevents the wheel hub assembly from falling off once control arm is disconnected.

- Remove all bolt points as mentioned above. Hardest one will be the rear due to lack of space and tight gaps. Breaker bar with long/regular sockets at the top to lock bolt from spinning while breaking the nut below. The rest requires a combination of spanners and breaker bar + sockets (easy). You may find that you have to remove the sway bar end link to free the control arm up for removal. If you can avoid this then great!

- If you have trouble with taking out the bolts from the front smaller bush and shock bolt after loosening the nuts out, combine a large socket (32mm/1-1/4 socket impact prefered or smaller) and a wobble extension and fit in reverse (inside of socket) and use a hammer. And just gently tap it out. Gently because you don't want to damage the threads if you punch it out too hard. They should just slide right off with the threads intact if done right. Also a pry bar is useful in this situation if you can find the appropriate leverage to use it.

- Gently shift wheel hub assembly off and away from control arm ball joint. This will give the necessary space to wiggle the control arm out once all bolt points are removed.

- Lightly & gently hammer front bush down whilst CAREFULLY keeping an eye on the rear larger bush. Due to the awkwardness of the sitting position of the lower control arm, the rear will tilt upwards when trying to remove. So be aware and this will cause a risk to hitting the brake fluid and fuel lines.

- Lightly hammer down the mid section of the control arm close to the shock where the nut & bolt is connected to push it down. Again CAREFULLY watching the rear larger bush.

- Slowly and lightly pull control arm towards you whilst still keeping an eye on the rear larger bush. Once that larger bush is free and out then the whole control arm comes out.

- Keep the rubber inserts from the smaller bush. Don't throw them out. They help dampen the forward/backward movements of this bush. Luckily the aftermarket bushes fits perfectly with these. You get 2x on both sides. Best to clean them with brake cleaner before install.

Taking out the bushes:

There's a couple options already covered by rusty's thread. I went a different approach with a sawzall and bush press kit with a homemade setup due to the lack of options I had doing this at home and not in a workshop.

*IMPORTANT* - Prior to taking out the rear larger bush you are required to mark a few points on both the OEM & aftermarket bush with the bracket for optimum alignment on the bolt holes to the subframe:
1. MARK how far in the OEM bush is pressed into the control arm
2. MARK on the bush bracket the direction of pressing in the bush (ie Inside-Outside) - This is to ensure you have the bracket in the correct install position to the subframe bolt holes. If your new bush comes fitted with a new bracket mark that one.
3. MARK the angle in which the new bush bracket aligns with the control arm marking a line on one of the tips of the bracket. Use the "bulge" line running down through the control arm as a guide. Can't miss it. This also ensures bracket is sitting correctly to the subframe bolt holes.

Removing bracket from larger bush: Because my new aftermarket bush came with a brand new bracket I skipped this part. But if you have to retain the old bracket and re-press into the new bush I believe you can just press it out of the old bush with traditional press tools. There should be enough clearance to fit a press tool around the bracket to press it out. A press machine is prefered for quickest time and least amount of effort.

Sawzall method (larger bush): Just like the DIY for the diff bush on our 370z, you very carefully and slowly cut directly right down just before inner metal shaft where the larger bush comfortable and tightly fits. Be aware that fluid is housed within this bush so be prepared for it to leak out. Prior to this you can drill holes to remove fluid beforehand. BE VERY WARY not to damage or even scratch the inner metal shaft where the large bush is pressed and fitted into the control arm. You can also drill+cut out some of the rubber material to get a better view as you cut further down. It's recommended to go very very slow as you cut the final inner metal ring of the bush. If done right it will give and make a crack sound. STOP once this happens. You can then just lightly punch it out or even just wiggle it out. Again emphasis on little to no damage on the inner metal shaft of the control arm where this large bush is pressed in.

Bush press kit or press machine (smaller bush): Pretty straight forward. The smaller bush is your traditional press out the old bush and press in the new one. A lot easier with a press machine if you have the option to use one. More effort with a bush press kit especially doing it at home as I've found.

Hot tip #1: Clean down control arm with brake cleaner especially where the 2 bushes were pressed in. Optional: Apply light grease on the larger bush inner metal housing and the metal housing on the control arm for the smaller bush for ease of press install.

Press in Larger bush with bracket installed: Make sure you have marked all key points from above before pressing in the large bush. Failure to do so will cause a miss-alignment on the bolt holes to the sub-frame and a full hard day's work wasted. Assuming you have all the necessary pressing tools. Carefully sit the bush as evenly as possible onto the metal shaft and rotate it around to align that "bulge" line on the control arm to the bush bracket (by now you will have found that it's one of the tips of the bracket that you need to align). Once you are happy with the alignment push it in enough so that it is secure and won't fall off or move while you set up the bush press tool. Then it's just as simple as pressing it in ever so slowly whilst keeping an eye on that "bulge" line alignment to the bracket. This is important so that you have no issues in fitting the larger bush back into the subframe bolts. Also ensure that the bush is pressed in at exactly the same distance as the old one. To avoid further headaches you're better off pressing in just before your marked point on the shaft. This way you can adjust accordingly how much more you need to press in. You want to avoid going too far in as this large bush is extremely difficult to press out unless you have the proper press tools or a press machine. Just make sure that about 1-2 mm/0.03-0.07inches off is tolerated to align the bolt holes. Anymore or too far off the alignment and this will cause the bolts to bend when you torque them down which is a big no no.

Control arm Installation:

Everything is reversed except for one key important procedure:
You need to jack the control arm up to reverse the awkward "tilting" of the rear larger bush so the bolts are aligned and ready for installation. Ensure first that all bolt points are aligned with the shock nut+bolts and front smaller bush nut+bolts are partially connected (not fully tightened) before doing this.

Hot tip #2: If you have trouble with pushing in the control arms into their bolt holes, you can use grease or some good ol' wd-40 lubricant on the surfaces to help with the metal on metal contact when aligning the bolt holes perfectly. After everything is aligned well and and good just spray it down with brake cleaner before tightening down with torque specs.

Important Note: A wheel alignment is required after this DIY as your toe will be affected on the front.

In the future I'll revise this as a proper DIY guide with pics. I've still got to do the other control arm as I only had time to do one side. But I'll take pics for better clarity.

I'm really surprised that this DIY for our front suspension on the z34 is not frequently discussed on this 370z forum. But hopefully this guide will help others out there.

Stay tuned.

Update 18/4/21 - Added more notes for more detail

04-16-2021, 07:57 PM	#2 (permalink)
ZPWR Base Member Join Date: Sep 2020 Location: Australia Posts: 31 Drives: 2012 370z Sport Rep Power: 3385	Alright. Just to update this thread of mine. I managed to DIY one of the front lower control arms. Removal and installation is pretty straight forward. I may write something up in the future about a specific DIY for the Front lower control arm bushes as I can't find any other posts related to this apart from Rusty's SPL control arm bushes thread found in this link: The Complete SPL Front Suspension The main reasons for this DIY are maintenance issues related to suspension noise and/or steering issues as well as modifying the bushes to better quality & longer lasting materials instead of the factory hydro-filled bushes that crap out so early. The benefits of doing this is greater stability in forward and backward motions of the car making it more stiff which I guess in a way also improves the handling. And you also won't have to worry about repairing these control arms ever again after this DIY. Due to the revised and upgraded suspension design of the z34 compared to the z33 (350z), the double wishbone control arms on the front especially the lower control arm on our 370z are a real B$-word to maintain and repair due to the tight spaces and exposed brake fluid and fuel lines on both sides that you have to pay special close attention to not to break or even accidentally "bump" as you remove/install the lower control arms. It's super awkward and requires abit of mechanical skill to work around with the whole front wheel hub assembly. A second pair of hands definitely helps. But not too difficult for the determined few who enjoy DIYs. This is one of the more challenging yet rewarding ones imo. Considering what options you have to remove and refit the bushes which is the part I struggled the most in this DIY as a backyarder. But a quick write up of what I did to make this possible with aftermarket bushes (like SPL) for all you DIY'ers out there who are thinking of doing this yourself: - Jack front of car, ensure park brake is on, chock rear wheels for added safety, wheels off, inspect bolted points for lower control arms. - Bolt points control arm - Ball joint nut, sway bar end link to shock bolt and nut, front impact small bush bolt & nut, rear large bush bolt & nut. - MUST Jack akebono brake assembly preferrably on the disc (helps to have brake pedal temporarily pressed in to prevent disc from rotating) BEFORE removal of control arm. Ensure disc is sitting securely. This prevents the wheel hub assembly from falling off once control arm is disconnected. - Remove all bolt points as mentioned above. Hardest one will be the rear due to lack of space and tight gaps. Breaker bar with long/regular sockets at the top to lock bolt from spinning while breaking the nut below. The rest requires a combination of spanners and breaker bar + sockets (easy). You may find that you have to remove the sway bar end link to free the control arm up for removal. If you can avoid this then great! - If you have trouble with taking out the bolts from the front smaller bush and shock bolt after loosening the nuts out, combine a large socket (32mm/1-1/4 socket impact prefered or smaller) and a wobble extension and fit in reverse (inside of socket) and use a hammer. And just gently tap it out. Gently because you don't want to damage the threads if you punch it out too hard. They should just slide right off with the threads intact if done right. Also a pry bar is useful in this situation if you can find the appropriate leverage to use it. - Gently shift wheel hub assembly off and away from control arm ball joint. This will give the necessary space to wiggle the control arm out once all bolt points are removed. - Lightly & gently hammer front bush down whilst CAREFULLY keeping an eye on the rear larger bush. Due to the awkwardness of the sitting position of the lower control arm, the rear will tilt upwards when trying to remove. So be aware and this will cause a risk to hitting the brake fluid and fuel lines. - Lightly hammer down the mid section of the control arm close to the shock where the nut & bolt is connected to push it down. Again CAREFULLY watching the rear larger bush. - Slowly and lightly pull control arm towards you whilst still keeping an eye on the rear larger bush. Once that larger bush is free and out then the whole control arm comes out. - Keep the rubber inserts from the smaller bush. Don't throw them out. They help dampen the forward/backward movements of this bush. Luckily the aftermarket bushes fits perfectly with these. You get 2x on both sides. Best to clean them with brake cleaner before install. Taking out the bushes: There's a couple options already covered by rusty's thread. I went a different approach with a sawzall and bush press kit with a homemade setup due to the lack of options I had doing this at home and not in a workshop. *IMPORTANT* - Prior to taking out the rear larger bush you are required to mark a few points on both the OEM & aftermarket bush with the bracket for optimum alignment on the bolt holes to the subframe: 1. MARK how far in the OEM bush is pressed into the control arm 2. MARK on the bush bracket the direction of pressing in the bush (ie Inside-Outside) - This is to ensure you have the bracket in the correct install position to the subframe bolt holes. If your new bush comes fitted with a new bracket mark that one. 3. MARK the angle in which the new bush bracket aligns with the control arm marking a line on one of the tips of the bracket. Use the "bulge" line running down through the control arm as a guide. Can't miss it. This also ensures bracket is sitting correctly to the subframe bolt holes. Removing bracket from larger bush: Because my new aftermarket bush came with a brand new bracket I skipped this part. But if you have to retain the old bracket and re-press into the new bush I believe you can just press it out of the old bush with traditional press tools. There should be enough clearance to fit a press tool around the bracket to press it out. A press machine is prefered for quickest time and least amount of effort. Sawzall method (larger bush): Just like the DIY for the diff bush on our 370z, you very carefully and slowly cut directly right down just before inner metal shaft where the larger bush comfortable and tightly fits. Be aware that fluid is housed within this bush so be prepared for it to leak out. Prior to this you can drill holes to remove fluid beforehand. BE VERY WARY not to damage or even scratch the inner metal shaft where the large bush is pressed and fitted into the control arm. You can also drill+cut out some of the rubber material to get a better view as you cut further down. It's recommended to go very very slow as you cut the final inner metal ring of the bush. If done right it will give and make a crack sound. STOP once this happens. You can then just lightly punch it out or even just wiggle it out. Again emphasis on little to no damage on the inner metal shaft of the control arm where this large bush is pressed in. Bush press kit or press machine (smaller bush): Pretty straight forward. The smaller bush is your traditional press out the old bush and press in the new one. A lot easier with a press machine if you have the option to use one. More effort with a bush press kit especially doing it at home as I've found. Hot tip #1: Clean down control arm with brake cleaner especially where the 2 bushes were pressed in. Optional: Apply light grease on the larger bush inner metal housing and the metal housing on the control arm for the smaller bush for ease of press install. Press in Larger bush with bracket installed: Make sure you have marked all key points from above before pressing in the large bush. Failure to do so will cause a miss-alignment on the bolt holes to the sub-frame and a full hard day's work wasted. Assuming you have all the necessary pressing tools. Carefully sit the bush as evenly as possible onto the metal shaft and rotate it around to align that "bulge" line on the control arm to the bush bracket (by now you will have found that it's one of the tips of the bracket that you need to align). Once you are happy with the alignment push it in enough so that it is secure and won't fall off or move while you set up the bush press tool. Then it's just as simple as pressing it in ever so slowly whilst keeping an eye on that "bulge" line alignment to the bracket. This is important so that you have no issues in fitting the larger bush back into the subframe bolts. Also ensure that the bush is pressed in at exactly the same distance as the old one. To avoid further headaches you're better off pressing in just before your marked point on the shaft. This way you can adjust accordingly how much more you need to press in. You want to avoid going too far in as this large bush is extremely difficult to press out unless you have the proper press tools or a press machine. Just make sure that about 1-2 mm/0.03-0.07inches off is tolerated to align the bolt holes. Anymore or too far off the alignment and this will cause the bolts to bend when you torque them down which is a big no no. Control arm Installation: Everything is reversed except for one key important procedure: You need to jack the control arm up to reverse the awkward "tilting" of the rear larger bush so the bolts are aligned and ready for installation. Ensure first that all bolt points are aligned with the shock nut+bolts and front smaller bush nut+bolts are partially connected (not fully tightened) before doing this. Hot tip #2: If you have trouble with pushing in the control arms into their bolt holes, you can use grease or some good ol' wd-40 lubricant on the surfaces to help with the metal on metal contact when aligning the bolt holes perfectly. After everything is aligned well and and good just spray it down with brake cleaner before tightening down with torque specs. Important Note: A wheel alignment is required after this DIY as your toe will be affected on the front. In the future I'll revise this as a proper DIY guide with pics. I've still got to do the other control arm as I only had time to do one side. But I'll take pics for better clarity. I'm really surprised that this DIY for our front suspension on the z34 is not frequently discussed on this 370z forum. But hopefully this guide will help others out there. Stay tuned. Update 18/4/21 - Added more notes for more detail Last edited by ZPWR; 04-18-2021 at 12:15 AM.