Bronze bushing change on

[Ricky Beals]

When I purchased this rd I knew the Trunnion needed replaced. I read where a lot of people had replaced their Trunnion with polyurethane. I was able to reach out to ATRO to see what was available for my truck. Jay at ATRO said they didn’t have a replacement for the bronze bushings and as far as he knew I would need to go with them. Has anybody here changed out bronze to polyurethane and if so what company did you use. Rear suspension is 44,000

Edited March 12, 2022 by Ricky Beals

[MACKS]

There is no such thing as polyurethane bushings to replace bronze,you have that confused with the pads,just a heads up if your bronze bushings are completely worn thru,u will most likely need to replace the bar and the saddles or it won’t be 100 percent,big expensive job,are u thinking of doing this yourself,I would not advise it..

[terry]

25 minutes ago, MACKS said:

There is no such thing as polyurethane bushings to replace bronze,you have that confused with the pads,just a heads up if your bronze bushings are completely worn thru,u will most likely need to replace the bar and the saddles or it won’t be 100 percent,big expensive job,are u thinking of doing this yourself,I would not advise it..

I second what MACKs says about the trunnion bushings, if it is bronze and really walking out, trunnion tube is probably gone too!    terry

[Ricky Beals]

I was going to assist a older gentleman that has done a few in the past. I like to at least have some knowledge of what’s going on. I didn’t see any cracks in bar where they enter the saddle on inside of truck. I’m really hoping those saddle’s and bar are not needing replaced. I’m hoping all that’s needed is to replace the bushings and pads. Truck has always been in Arkansas so rust shouldn’t be an issue. I may call axle surgeons of arkansas Monday and see if they know of a qualified spring shop that has done a lot of mack Trunnion. I think we can do the swap if it’s just a bushing exchange but probably going be out gunned if bar and saddle has to be replaced.

 

Can you guys offer me any idea on how to check and see how bad Trunnion is. Or is this something that will not be known until everything is off and your looking at the bare bar.

[Ricky Beals]

And yes Macks I did think that I could replace the bronze bushing with a polyurethane bushing. After talking with ATRO he explained to me that ATRO didn’t make a poly bushing to replace the bronze original. If I understand you correctly your saying there is no poly replacement and it has to be replaced with original bronze bushing.

[MACKS]

23 minutes ago, Ricky Beals said:

And yes Macks I did think that I could replace the bronze bushing with a polyurethane bushing. After talking with ATRO he explained to me that ATRO didn’t make a poly bushing to replace the bronze original. If I understand you correctly your saying there is no poly replacement and it has to be replaced with original bronze bushing.

Yes that’s correct,only bronze,once u get it apart and inspect the bushings if there worn all the way thru then the bar and the saddle will have wear since they were contacting each other,new saddles come with the bushings already pressed in,you might want to check out Stengel bros on line and u can price every thing out,I think they have the best prices ..

[Ricky Beals]

Ok I understand it looks like I will know when it gets tore down. Looks like I’m going to need to inspect those bushings and hope like hell it’s all good. My older friend is a welder/fabricator. The area sees a lot of log trucks but for some reason not a lot of Mack’s in our area. Thanks for the input.

[MACKS]

To check,back the truck up while turning hard one way and then the other look to see if the wheel are moving out of line,they should stay perfectly straight or you can jack it up under the trunnion bar on one side and get a big bar in between the spring and the frame rail and pry it outward to check for movement..

[mechohaulic]

43 minutes ago, MACKS said:

To check,back the truck up while turning hard one way and then the other look to see if the wheel are moving out of line,they should stay perfectly straight or you can jack it up under the trunnion bar on one side and get a big bar in between the spring and the frame rail and pry it outward to check for movement..

if he's unsure of the process ; couldn't  he just take off the end cap (which has to come off anyway at some point), remove nut and hardware  . clean off hopefully some grease and see the gap between bushing and tube ?

[MACKS]

34 minutes ago, mechohaulic said:

if he's unsure of the process ; couldn't  he just take off the end cap (which has to come off anyway at some point), remove nut and hardware  . clean off hopefully some grease and see the gap between bushing and tube ?

He could do that,I just think he should check the actual movement of the springs,see how much the rears are walking out,if it’s just slight he could just keep on hauling.

[Ricky Beals]

The wheels walk I have driven it backwards with the bed up. Have not made a sharp turn with the bed up. Tie rods bushings are coming out. I have two that are in line with drive shaft. I have to pull the big dump cylinder to have it repacked. I have a 32,000 lb excavator. I wondering if I shouldn’t take that dump bed off before I do all of this. After I release the big cylinder and hoses nothing holding it on but two pins at the rear. Take them out and lift that bed off.

 

I can take a video of driving it backwards with turning tight radius and showing how much it walks out. It will be next week when I’m down there.

macks so I understand your process place jack under say drivers trunion. Jack up till both sets of tires are off the ground? Then wedge big bar between springs and frame and check for movement. 

[Ricky Beals]

Mechohaulic it has grease zerks on outer top but the drivers has broken off so I’m betting it hasn’t seen grease in a long time

You thinking taking off cap, nut with bolt, two washers and check for up and down movement

[MACKS]

22 minutes ago, Ricky Beals said:

The wheels walk I have driven it backwards with the bed up. Have not made a sharp turn with the bed up. Tie rods bushings are coming out. I have two that are in line with drive shaft. I have to pull the big dump cylinder to have it repacked. I have a 32,000 lb excavator. I wondering if I shouldn’t take that dump bed off before I do all of this. After I release the big cylinder and hoses nothing holding it on but two pins at the rear. Take them out and lift that bed off.

 

I can take a video of driving it backwards with turning tight radius and showing how much it walks out. It will be next week when I’m down there.

macks so I understand your process place jack under say drivers trunion. Jack up till both sets of tires are off the ground? Then wedge big bar between springs and frame and check for movement. 

Yes but if your seeing the rears walking out bad no sense might as well rebuild it if u have the bucks to do it right..

[mechohaulic]

when comments are made it's based on :: 1=not knowing experience of poster for doing a project. 2= the schedule a vehicle has for being down for repairs. 3= the $$$$$ a person has for a project. 

[Onyx610]

So not to go against the grain here, but if you would like to do the job and you have a knowledgeable guy to help you I’d say go for it. Only if you don’t need a trunnion stand and If you plan on doing springs too. You can get the whole spring assembly already put together and u bolts already torqued. Basically slide it on and put the few pieces on the shaft.  
 

 

[Joey Mack]

I bet he can rattle the box rubbers by hand, and i like the idea of taking the end cap off, as well as jacking up on the trunnion bar.  it would be good to have a helper run the jack while you look at the end of the trunnion.  I have used a company call Carolina axle surgeons... I think you can just go to the 'web' and look up axle surgeons near you, and one will pop up.. the last one I had done was a few years ago, and it was $1500.00 parts and labor. all you have to do is remove the wheels and the springs and leave stands under the frame rails. they will cut ou the old bar and weld in a new one..  Of course if the 'A frame' is rusted through,  well that changes everything..  Good luck Ricky.... jojo

[Ricky Beals]

Yes sir I purchased it thinking I had to replace bushings. The black insulators look good but I can see where one of the T’s have rubbed the box. Going replace them also with ATRO poly

[Mark T]

You sorta need to know what you're looking at to determine how extensive a repair would be needed. There's a lot that can be worn on the suspension and when it's all worn ?  then there's lots of movement . Replacing a trunion stand is a huge job on a dump truck, even for a regular spring shop. You need to find a place familiar with Macks who could be honest with you about what needs to be replaced.  (lol)  lots of guys like to think the rubber pads at the end of the springs cure everything. Maybe a new torque rod too,  cause they're the cheapest component.....it's usually not the rubber pads or as simple as a torque rod .  Just say'n.   Worst case the repair easily reach 5 figures on a dump truck.

[MACKS]

1 hour ago, Mark T said:

You sorta need to know what you're looking at to determine how extensive a repair would be needed. There's a lot that can be worn on the suspension and when it's all worn ?  then there's lots of movement . Replacing a trunion stand is a huge job on a dump truck, even for a regular spring shop. You need to find a place familiar with Macks who could be honest with you about what needs to be replaced.  (lol)  lots of guys like to think the rubber pads at the end of the springs cure everything. Maybe a new torque rod too,  cause they're the cheapest component.....it's usually not the rubber pads or as simple as a torque rod .  Just say'n.   Worst case the repair easily reach 5 figures on a dump truck.

That’s the truth,and the reason I say if in doubt go with all new parts but I forgot the trunnion bar is not removable like on the 58, that could be a real cost factor if it’s shot..

[Ricky Beals]

The truck is my personal truck. I worked as an Insurance agent for 27 years and built a nice business. The company I worked for figured out a way to get out of their contract and well they did. I have known for a few years that I was very unhappy with the life I had. When the job ended and it just ended I asked my wife of 30 years if she would move back home where I grew up. I have always wanted a dump truck, excavator and bull dozer. A lot of folks including my wife say I’m a little crazy, might just be. I got the excavator and dump truck and hauled 30 loads of gravel for a house and shop pad.  Not one time did I ever think I was working. At first I didn’t like digging near the edge with excavator but I got some seat time and now it doesn’t bother me at all.  I bought the wrong dump truck and made my first post on here about changing out the front springs. It was a mack tractor that was converted to a dump. I then sold that dump and bought the RD688 and I think it’s a good truck. To me this is fun and I definitely understand my limitations. Would never try and rebuild the motor, tranny or rearend. This I think I can do with my buddies help. If the Trunnion bar and saddles are good than it was a good call. If not then I will probably post up here and see what my options are. 
 

Macks what is rebuilt back right?
I have looked the springs over and not one is broke. Do they need replaced? If not then I’m going to assume everything from saddle back to cover gets replaced. On Insulators ATRO makes a kit that has all the bolts and pads. Should be good there.  I’m paying the guy helping me but he is also a friend. He will be out of pocket for a few weeks but we should get this down last week in March.

Mark T that’s what makes me a little hesitant. It’s a gamble and I know it. The money ain’t a problem because I have already set it aside. I’m OCD and know I will do it right. If we end up with a bad bar or saddle’s then we are over our head. I will be calling Axle surgeons of Arkansas. Think I’m going try it. It may even be fun and I definitely learn a few things. 

[MACKS]

27 minutes ago, Ricky Beals said:

The truck is my personal truck. I worked as an Insurance agent for 27 years and built a nice business. The company I worked for figured out a way to get out of their contract and well they did. I have known for a few years that I was very unhappy with the life I had. When the job ended and it just ended I asked my wife of 30 years if she would move back home where I grew up. I have always wanted a dump truck, excavator and bull dozer. A lot of folks including my wife say I’m a little crazy, might just be. I got the excavator and dump truck and hauled 30 loads of gravel for a house and shop pad.  Not one time did I ever think I was working. At first I didn’t like digging near the edge with excavator but I got some seat time and now it doesn’t bother me at all.  I bought the wrong dump truck and made my first post on here about changing out the front springs. It was a mack tractor that was converted to a dump. I then sold that dump and bought the RD688 and I think it’s a good truck. To me this is fun and I definitely understand my limitations. Would never try and rebuild the motor, tranny or rearend. This I think I can do with my buddies help. If the Trunnion bar and saddles are good than it was a good call. If not then I will probably post up here and see what my options are. 
 

Macks what is rebuilt back right?
I have looked the springs over and not one is broke. Do they need replaced? If not then I’m going to assume everything from saddle back to cover gets replaced. On Insulators ATRO makes a kit that has all the bolts and pads. Should be good there.  I’m paying the guy helping me but he is also a friend. He will be out of pocket for a few weeks but we should get this down last week in March.

Mark T that’s what makes me a little hesitant. It’s a gamble and I know it. The money ain’t a problem because I have already set it aside. I’m OCD and know I will do it right. If we end up with a bad bar or saddle’s then we are over our head. I will be calling Axle surgeons of Arkansas. Think I’m going try it. It may even be fun and I definitely learn a few things. 

Yeah u can do it it’s not brain surgery,lol,just be careful make sure u support the truck properly and have at it,let’s us know what u find when u get it apart,good luck..

[Ricky Beals]

I’m thinking that when you guys say do it right your talking springs, and the whole bit. Which makes the video Onyx610 posted (which I watched) spot on. If doing it right means replacing the springs might as well get the kit in the video where it’s already done. Just installing the springs and insulators. 

[MACKS]

10 minutes ago, Ricky Beals said:

I’m thinking that when you guys say do it right your talking springs, and the whole bit. Which makes the video Onyx610 posted (which I watched) spot on. If doing it right means replacing the springs might as well get the kit in the video where it’s already done. Just installing the springs and insulators. 

That would be the way to go if u got the bucks to throw at it, take it apart and see what the bar looks like,you’ll have to measure it and see if it’s within spec or at least close..

[Onyx610]

Plus your not gonna get any closer! So if you have the money I would do it. Then you know that whole rear suspension is good to go. Also it’s gonna make that job much easier getting it all in one piece. 

[Onyx610]

Those u bolts are torqued to something like 1400 ft/lbs. 😯