Lower a arm bushing replacement help - The 1947 - Present Chevrolet & GMC Truck Message Board Network

wpavlis · 03-08-2021, 12:06 AM

Hello. I haven't posted in a while. I have been just enjoying driving the truck around on the weekends rather than working on the old girl. I have a replacement set of a-arms that i had powder coated and decided to assemble them so that i can get them installed sometime in the next few weeks. I read several threads on here and read the instructions in the factory manual. I centered the shaft as best i could and got the threads on the bushings started. I ran them in 1 turn at a time until they tightened up and then torqued them down. For some reason the shaft no longer seems to be centered. Should i back them out and try again? The manual mentions some measurement of 3/4 inch, but i don't really understand where to verify this measurement. Any advice would be appreciated. Thanks!

**pjmoreland** · 03-08-2021, 01:01 AM

If you turn the shaft by hand, it will thread out of one cap and into the other. You can turn it as far as it will go one way and then turn it as far as it will go the other way and then split the difference to put it in the middle.

Accelo · 03-08-2021, 01:48 AM

This is very easy to get off center.

It can easily be one thread pitch off.
I can't remember if the large nuts started on the A arm while the cross shaft was still loose or not.
Try this;
Mark each nut so you can track the number of turns.
Start each nut and rotate 1/2 turn.
If the center shaft is still loose turn each nut 1/2 turn at a time till the shaft is centered. Then hold the center shaft stationary while alternating tightening the nuts from side to side. This will keep you from crushing the A arm.

Sometimes they come out perfect and the center shaft can still be rotated by hand. Sometimes it takes considerable force. Hopefully you will get lucky and they will rotate by hand.

Bad news is the nuts rotate hard and one has to resist the temptation to use an impact wrench and it makes it impossible to count the turns.

Wish I would have written this up when I did the assembly. Common to have to do this several times. Protecting the A arm finish during this assembly process is difficult.

**Grumpy old man** · 03-08-2021, 07:27 AM

This thread should help .

https://www.67-72chevytrucks.com/vbo...d.php?t=799774

http://67-72chevytrucks.com/vboard/s...d.php?t=795425

**1972BackInBlackC10** · 03-08-2021, 09:21 PM

i bolted my cross shaft to my cross member and then put the a arm on, this way i didnt have to worry about the shaft moving around on me, then i put each cap on one full turn so i knew they wouldnt fall off on me and i marked each one with a paint marker so i had a reference point.

then i started tightening them equal amounts on each side. I started with 3 turns each side and then 2 until the threads were close to reaching the a arms, then i would go one turn at a time making sure the same amount of threads were showing on each cap as i went along,

you can center the a arm on the shaft but its not too important until the non threaded ends of the caps are in each hole then start paying attention to, thats how i did mine and i had no issues

03-08-2021, 12:06 AM	#1
wpavlis Registered User Join Date: Oct 2015 Location: San Tan Valley, Arizona Posts: 313	Lower a arm bushing replacement help Hello. I haven't posted in a while. I have been just enjoying driving the truck around on the weekends rather than working on the old girl. I have a replacement set of a-arms that i had powder coated and decided to assemble them so that i can get them installed sometime in the next few weeks. I read several threads on here and read the instructions in the factory manual. I centered the shaft as best i could and got the threads on the bushings started. I ran them in 1 turn at a time until they tightened up and then torqued them down. For some reason the shaft no longer seems to be centered. Should i back them out and try again? The manual mentions some measurement of 3/4 inch, but i don't really understand where to verify this measurement. Any advice would be appreciated. Thanks! Attached Images

03-08-2021, 01:01 AM	#2
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,300	Re: Lower a arm bushing replacement help If you turn the shaft by hand, it will thread out of one cap and into the other. You can turn it as far as it will go one way and then turn it as far as it will go the other way and then split the difference to put it in the middle.

03-08-2021, 01:48 AM	#3
Accelo Registered User Join Date: Mar 2015 Location: washington Posts: 2,157	Re: Lower a arm bushing replacement help This is very easy to get off center. It can easily be one thread pitch off. I can't remember if the large nuts started on the A arm while the cross shaft was still loose or not. Try this; Mark each nut so you can track the number of turns. Start each nut and rotate 1/2 turn. If the center shaft is still loose turn each nut 1/2 turn at a time till the shaft is centered. Then hold the center shaft stationary while alternating tightening the nuts from side to side. This will keep you from crushing the A arm. Sometimes they come out perfect and the center shaft can still be rotated by hand. Sometimes it takes considerable force. Hopefully you will get lucky and they will rotate by hand. Bad news is the nuts rotate hard and one has to resist the temptation to use an impact wrench and it makes it impossible to count the turns. Wish I would have written this up when I did the assembly. Common to have to do this several times. Protecting the A arm finish during this assembly process is difficult.

03-08-2021, 07:27 AM	#4
Grumpy old man Senior Member Join Date: Dec 2013 Location: Gods country East,Tn Posts: 8,545	Re: Lower a arm bushing replacement help This thread should help . https://www.67-72chevytrucks.com/vbo...d.php?t=799774 http://67-72chevytrucks.com/vboard/s...d.php?t=795425 __________________ 1967 Factory short bed - Old school '71 - 350 / 4bolt / 487 heads / Edelbrock C3BX Muncie M-22 4 speed / Hurst Comp plus Factory 12 bolt posi 3.73 / 255-70-15 Smoothed firewall / Factory cowl induction Power disc brakes / power steering / 3.5-5" drop Last edited by Grumpy old man; 03-08-2021 at 07:36 AM.

03-08-2021, 09:21 PM	#5
1972BackInBlackC10 Senior Member Join Date: Jan 2012 Location: Estevan, Saskatchewan Posts: 1,025	Re: Lower a arm bushing replacement help i bolted my cross shaft to my cross member and then put the a arm on, this way i didnt have to worry about the shaft moving around on me, then i put each cap on one full turn so i knew they wouldnt fall off on me and i marked each one with a paint marker so i had a reference point. then i started tightening them equal amounts on each side. I started with 3 turns each side and then 2 until the threads were close to reaching the a arms, then i would go one turn at a time making sure the same amount of threads were showing on each cap as i went along, you can center the a arm on the shaft but its not too important until the non threaded ends of the caps are in each hole then start paying attention to, thats how i did mine and i had no issues



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