Fj80 axle/coil swap
- Thread starter EarthX
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This is one of the coolest thing I've ever seen!!!!
Nice work! I have also always liked your 60. 
i likes the build........
- Thread starter
- #27
Is that an 80 arm on a 60 box? If so, could you tell me how much room there is between the castle nut and the frame. I'm looking for a pitman arm w/ less drop than my Marlin arm.
Thanks!
Nope sorry. That the oem 80 arm
Putting coils on my 62 has always been in the plans, but it won't happen for a few years. I will probably end up keeping my factory front axle and using Cage Offroad radius arms, a one-off panhard and some nice coilovers. I'd love to compare the ride of the coils to the standard leaf springs. I'm betting it will be cush.
- Thread starter
- #33
Well not much new as of now. I had a few hours to work on it this week but it looks about the same. I do have a question though, might be better to ask in the 80's section, but oh well. Im looking into running FRONT 80 coils in the REAR due to it being very tight back there. What are the differences in the front and rear springs? The front should be stiffer due to the motor no? Any help would be great. Cheers
Cruiser Outfitters
This should help you if going OME. It doesn't have the stock rates. Actually the rates vary quite a bit by year and whether it had 3rd row seats. Even the number of wraps on the coils varies from application and year. Maybe one of the 4Runner guys has figured them out? The later model ones are using the front stock 80 coils to get about a 3.5" lift for their 4 Runners.
I hadn't seen your project before I'm definitely interested. I'm working on dropping a 60 body on an 80 chassis right now, I have a new set of OME J springs sitting on the shelf for that part of the project. But that isn't why I'm interested. I think I picked up another 60 today and I immediately thought to myself I need to put coils on it.
And I've been there and done that, hacking up an 80 frame for the mounts. A friend of mine is putting 80 suspension under his 55. It is a pain. However, I came away with a real respect for how stout Toyota frames really are.
The coolest suspension set up I've seen is a military jeep buggy running air shocks (no coilovers). It flexed awesome but what I liked about it is that it was completely quiet. The only thing you could hear was the tires squeeking on the rocks. No clanking or binding suspension sounds. It would be tough to engineer something like this in a full bodied wagon.
One last thing, dropping down on rocks with 80 front control arms is no big deal (someone commented on this). They actually slide better than leaf springs, especially if you have to go backwards.
This should help you if going OME. It doesn't have the stock rates. Actually the rates vary quite a bit by year and whether it had 3rd row seats. Even the number of wraps on the coils varies from application and year. Maybe one of the 4Runner guys has figured them out? The later model ones are using the front stock 80 coils to get about a 3.5" lift for their 4 Runners.
I hadn't seen your project before I'm definitely interested. I'm working on dropping a 60 body on an 80 chassis right now, I have a new set of OME J springs sitting on the shelf for that part of the project. But that isn't why I'm interested. I think I picked up another 60 today and I immediately thought to myself I need to put coils on it.
And I've been there and done that, hacking up an 80 frame for the mounts. A friend of mine is putting 80 suspension under his 55. It is a pain. However, I came away with a real respect for how stout Toyota frames really are.
The coolest suspension set up I've seen is a military jeep buggy running air shocks (no coilovers). It flexed awesome but what I liked about it is that it was completely quiet. The only thing you could hear was the tires squeeking on the rocks. No clanking or binding suspension sounds. It would be tough to engineer something like this in a full bodied wagon.
One last thing, dropping down on rocks with 80 front control arms is no big deal (someone commented on this). They actually slide better than leaf springs, especially if you have to go backwards.
- Thread starter
- #35
The later model ones are using the front stock 80 coils to get about a 3.5" lift for their 4 Runners.
They are putting the front 80 coils in the rear of the 4 runners?
And I've been there and done that, hacking up an 80 frame for the mounts. A friend of mine is putting 80 suspension under his 55. It is a pain. However, I came away with a real respect for how stout Toyota frames really are.
Amen. The fzj80 frame is BEEF. In some spots its triple walled!
The coolest suspension set up I've seen is a military jeep buggy running air shocks (no coilovers). It flexed awesome but what I liked about it is that it was completely quiet. The only thing you could hear was the tires squeeking on the rocks. No clanking or binding suspension sounds. It would be tough to engineer something like this in a full bodied wagon.
That would be nice but I plan to load this thing up with gear and tow. Neither of which would be too nice with air shocks.
One last thing, dropping down on rocks with 80 front control arms is no big deal (someone commented on this). They actually slide better than leaf springs, especially if you have to go backwards.
Exactly what i thought! Cheers
They are putting the front 80 coils in the rear of the 4 runners?
And I've been there and done that, hacking up an 80 frame for the mounts. A friend of mine is putting 80 suspension under his 55. It is a pain. However, I came away with a real respect for how stout Toyota frames really are.
Amen. The fzj80 frame is BEEF. In some spots its triple walled!
The coolest suspension set up I've seen is a military jeep buggy running air shocks (no coilovers). It flexed awesome but what I liked about it is that it was completely quiet. The only thing you could hear was the tires squeeking on the rocks. No clanking or binding suspension sounds. It would be tough to engineer something like this in a full bodied wagon.
That would be nice but I plan to load this thing up with gear and tow. Neither of which would be too nice with air shocks.
One last thing, dropping down on rocks with 80 front control arms is no big deal (someone commented on this). They actually slide better than leaf springs, especially if you have to go backwards.
Exactly what i thought! Cheers
So long as they are not a progressive wound coil spring, it is fairly easy to calculate the rate. A qwik google turned up this on-line calculator:
Pro Shock Coil Spring Rate Calculator
Another that might be a real bonus when fine tuning time comes along:
Sway-A-Way Calculators
If you want to see the math going on behind the scene:
Suspension Coil Spring Rate Design Equations Formulas Calculator
Others:
F-O-A OFF-ROAD Shock Absorbers
Coil Spring Rate Calculations by Wallace Racing
I believe that the air shocks mentioned are an air spring built into a monotube shock. Quite robust, but typically those are not good at carrying much weight or going very fast (temperature largely varies the spring rate). They are quite popular in light weight crawlers as they are simple and effective for that application.
What a friend has talked of doing, but has yet to actually do, is to put a single (large?) air spring at the center of the rear diff. It would carry the weight w/o having a huge effect on articulation. FFT
Pro Shock Coil Spring Rate Calculator
Another that might be a real bonus when fine tuning time comes along:
Sway-A-Way Calculators
If you want to see the math going on behind the scene:
Suspension Coil Spring Rate Design Equations Formulas Calculator
Others:
F-O-A OFF-ROAD Shock Absorbers
Coil Spring Rate Calculations by Wallace Racing
I believe that the air shocks mentioned are an air spring built into a monotube shock. Quite robust, but typically those are not good at carrying much weight or going very fast (temperature largely varies the spring rate). They are quite popular in light weight crawlers as they are simple and effective for that application.
What a friend has talked of doing, but has yet to actually do, is to put a single (large?) air spring at the center of the rear diff. It would carry the weight w/o having a huge effect on articulation. FFT
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- Thread starter
- #37
Thats would all be great if i knew the weight of my 60. As far as i understand, by figuring out spring rate ill know the static height of the spring when put under the weight of the truck, correct? Now a progressive spring(which an 80 spring is??) is another calculation? Math was never my best subject.
I really just want to know if it will work, what are the pros/cons.
I really just want to know if it will work, what are the pros/cons.
please excuse the noob question...
what's the advantages of doing this over just buying an 80 in the first place? is it just a $$ thing?
what's the advantages of doing this over just buying an 80 in the first place? is it just a $$ thing?
- Thread starter
- #39
Im doing it because I want to.
Reason enough? I just enjoy trying new things. Plus i like the 60 more than an 80. I have both but have always liked the 60 more. Cheers
Yes, Late model 4runners use the front 80 springs in the rear. Pre98 use the rear ones in rear. It has created a market for used 80 springs.
I saw your post over in the 80 section too. You might try to find some matched 80 springs. Get one Left Front from one rig and another Left Front from another. This would balance it out as the 60 rear end is pretty well balanced with the tank centered. And like I posted earlier, spring rates changed both front and rear several times. You can match them up by the colored dots. I'm thinking the tallest springs I've seen have been out of the FJ80s. I've parted a few 80s and lifted a lot of them. The lowest ones I've seen were out of an 97 LX w/ 3rd row seats. I've heard mixed reports about whether or not the LXs have the same springs. I've never done a 97 Cruiser so I couldn't compare them to the LX springs.
I saw your post over in the 80 section too. You might try to find some matched 80 springs. Get one Left Front from one rig and another Left Front from another. This would balance it out as the 60 rear end is pretty well balanced with the tank centered. And like I posted earlier, spring rates changed both front and rear several times. You can match them up by the colored dots. I'm thinking the tallest springs I've seen have been out of the FJ80s. I've parted a few 80s and lifted a lot of them. The lowest ones I've seen were out of an 97 LX w/ 3rd row seats. I've heard mixed reports about whether or not the LXs have the same springs. I've never done a 97 Cruiser so I couldn't compare them to the LX springs.