long travel rear: more harebrained schemes

[yotatake2]

Hey guys,

So I've been trying to figure out my future rear suspension setup for a while now. I was originally planning on doing a triangulated 4 link with extended upper links but soon realized the gas tank is in the way. I considered doing an inverted triangular 4 link, but the geometry of it makes the axle more prone to bending/twisting under impact to the wheel. Ideally, i'd like to keep my stock tank and not have to run a fuel cell because I want to retain the trunk space. So yesterday I came up with a crazy idea and wanted to run it by you guys.

Here goes. I'm considering remaking the rear linkages and mounting them on the stock pickup points but making them about 2-4 inches longer than stock depending on how much i can get away with. I understand I'd also have to get my drive shaft extended (or just find a slightly longer one if i get lucky) but I feel like this would be a good way to get extended, cleaner travel without putting my u joints under too much angle and stress. I'd also replace the panhard bar with a Watts linkage. Just to clear up a few issues, The rear fenders and bumper are going to be chopped up/remade. I still need to find a place that makes glass bedsides for the 3rd gen, or make custom ones with the wheel cutouts moved back. I'm going to be using a tundra axle with a custom coilover setup so don't worry about the stock location for the shocks or coils.
Sooooo what do y'all think?

 

[snivilous]

I was originally gonna do an inverted triangulated 4 link since I didn't want to move the tank either. Though after reading the write ups on moving the tank to the back I'm gonna go that route. Main reasoning being then I should be able to run a normal triangulation and the CG will be shifted back and centered and then I'll run a cantilever forwards between the links. Watts setups are sweet, if you haven't seen it a guy did that on TTORA (Dual Sport Build) and it's pretty sexy--though personally I'm not a big fan of the watts due to complexity and the fact a properly done 4-link is fully redundant.

I'll follow this though, I've started taking measurements to design my rear end and will start buying parts in a week or two.

 

[yotatake2]

I was originally gonna do an inverted triangulated 4 link since I didn't want to move the tank either. Though after reading the write ups on moving the tank to the back I'm gonna go that route. Main reasoning being then I should be able to run a normal triangulation and the CG will be shifted back and centered and then I'll run a cantilever forwards between the links. Watts setups are sweet, if you haven't seen it a guy did that on TTORA (Dual Sport Build) and it's pretty sexy--though personally I'm not a big fan of the watts due to complexity and the fact a properly done 4-link is fully redundant.

I'll follow this though, I've started taking measurements to design my rear end and will start buying parts in a week or two.

Do you have the link to any of those write-ups by any chance? Is it pretty involved? Also, do you mind if I ask why you decided to go inverted triangulated as opposed to traditional? If you move the tank, you would have room for either setup, correct?

Thanks.

 

[snivilous]

Do you have the link to any of those write-ups by any chance? Is it pretty involved? Also, do you mind if I ask why you decided to go inverted triangulated as opposed to traditional? If you move the tank, you would have room for either setup, correct?

Thanks.

http://www.toyota-4runner.org/3rd-gen-t4rs/194378-ford-f150-gas-tank-swap-into-2000-4runner.html

Dual Sport 4runner - Page 3 - TTORA Forum

And if I don't move the gas tank I would do the inverted, otherwise (which as of now I plan to do) I'll do a normal triangulation. As long as the axle is properly positioned I don't see a big issue running inverted/normal, though as I said I haven't gotten into the heavy research and design phase quite yet. My main goal is to get rid of the track bar and run coilovers without going into the body and pulling over 16" of (real) travel in the back.

 

[1985taylor1925]

Hey guys,

So I've been trying to figure out my future rear suspension setup for a while now. I was originally planning on doing a triangulated 4 link with extended upper links but soon realized the gas tank is in the way. I considered doing an inverted triangular 4 link, but the geometry of it makes the axle more prone to bending/twisting under impact to the wheel. Ideally, i'd like to keep my stock tank and not have to run a fuel cell because I want to retain the trunk space. So yesterday I came up with a crazy idea and wanted to run it by you guys.

Here goes. I'm considering remaking the rear linkages and mounting them on the stock pickup points but making them about 2-4 inches longer than stock depending on how much i can get away with. I understand I'd also have to get my drive shaft extended (or just find a slightly longer one if i get lucky) but I feel like this would be a good way to get extended, cleaner travel without putting my u joints under too much angle and stress. I'd also replace the panhard bar with a Watts linkage. Just to clear up a few issues, The rear fenders and bumper are going to be chopped up/remade. I still need to find a place that makes glass bedsides for the 3rd gen, or make custom ones with the wheel cutouts moved back. I'm going to be using a tundra axle with a custom coilover setup so don't worry about the stock location for the shocks or coils.
Sooooo what do y'all think?

I started a thread on watts linkage a while back.

http://www.toyota-4runner.org/3rd-gen-t4rs/180841-anyone-here-have-watts-linkage-back.html


I think its a really cool idea, and you should do it. Theres a video in the above thread of an off road specific version of watts linkage called CRC which works very well. But CRC is ideal for wheeling/crawling where clearance is a huge factor. For more baja style long travel driving I dont think its really necessary. You could find a way to position the setup parallel to side of the axle and still have plenty of clearance. CRC would be a little more tricky with the limited space between the axle and frame/undercarriage. No one on this forum has tried watts linkage on a 3rd gen. I would love to do it myself, if I had the tools, time, and money. But you could be the first to step into this uncharted territory, and see how well it performs! I bet it would be awesome, as long as you use quality joints

 

[yotatake2]

http://www.toyota-4runner.org/3rd-gen-t4rs/194378-ford-f150-gas-tank-swap-into-2000-4runner.html

Dual Sport 4runner - Page 3 - TTORA Forum

And if I don't move the gas tank I would do the inverted, otherwise (which as of now I plan to do) I'll do a normal triangulation. As long as the axle is properly positioned I don't see a big issue running inverted/normal, though as I said I haven't gotten into the heavy research and design phase quite yet. My main goal is to get rid of the track bar and run coilovers without going into the body and pulling over 16" of (real) travel in the back.

Hmm, seriously considering that now. Although I'd probably just use the ford pump and sender as I don't have the patience to transfer all that stuff over lol. Only thing is I might need to eventually transfer the tundra pump over when i do the 4.7 swap.

 

[yotatake2]

I started a thread on watts linkage a while back.

http://www.toyota-4runner.org/3rd-gen-t4rs/180841-anyone-here-have-watts-linkage-back.html


I think its a really cool idea, and you should do it. Theres a video in the above thread of an off road specific version of watts linkage called CRC which works very well. But CRC is ideal for wheeling/crawling where clearance is a huge factor. For more baja style long travel driving I dont think its really necessary. You could find a way to position the setup parallel to side of the axle and still have plenty of clearance. CRC would be a little more tricky with the limited space between the axle and frame/undercarriage. No one on this forum has tried watts linkage on a 3rd gen. I would love to do it myself, if I had the tools, time, and money. But you could be the first to step into this uncharted territory, and see how well it performs! I bet it would be awesome, as long as you use quality joints

Thanks man. I would love to pioneer the watts linkage for our trucks, but at the end of the day, I'd definitely prefer a traditional 4 link. Less material and hardware without the watts setup and just simpler in general. I think I'm going to explore this gas tank relocation further. I like the idea of the improved weight distribution as well as being able to run a traditional 4 link. Plus, with the tank behind the axle, I eliminate the risk of damaging the tank if I high center.

 

[1985taylor1925]

Thanks man. I would love to pioneer the watts linkage for our trucks, but at the end of the day, I'd definitely prefer a traditional 4 link. Less material and hardware without the watts setup and just simpler in general. I think I'm going to explore this gas tank relocation further. I like the idea of the improved weight distribution as well as being able to run a traditional 4 link. Plus, with the tank behind the axle, I eliminate the risk of damaging the tank if I high center.

Yeah, either one will require a fair amount of fabrication. But I would think you would have to do more with a 4 link setup. With watts you could use the stock control arm locations and just extend them and add the watts setup. Either way Im looking forward to seeing what you design

 

[MojaveMadMan]

I think if you are going to go through all the work to build a custom link set up, no matter which style you go, then why not do the little bit of extra work to make a gas tank? When I was building custom off road pleasure and race cars we used to make our own gas tanks all the time. We would use some 0.090 thick aluminum, bend it to the desired shape and weld in the rest of the pieces. You could bolt a Toyota sending unit to the top, or build in a sump on the bottom of the tank and then use an off the shelf inline fuel pump and filter (no more gas gauge). I am sure you could find a welding/sheet metal shop to do the work for you for around $400 +/- depending on how complicated you design it.

Like I said, you are making new links, new pivots, modifying the body, mounting custom coilovers, etc. Why not just take a few extra steps and have a custom tank made and mount it behind the axle. Or hell, you could buy a generic rectangle tank and mount it behind the passenger seat or something like that if you really wanted to. Not to mention, you will probably save time on coilover mounts and stuff like that with the stock tank moved out of the way...

 

[yotatake2]

I think if you are going to go through all the work to build a custom link set up, no matter which style you go, then why not do the little bit of extra work to make a gas tank? When I was building custom off road pleasure and race cars we used to make our own gas tanks all the time. We would use some 0.090 thick aluminum, bend it to the desired shape and weld in the rest of the pieces. You could bolt a Toyota sending unit to the top, or build in a sump on the bottom of the tank and then use an off the shelf inline fuel pump and filter (no more gas gauge). I am sure you could find a welding/sheet metal shop to do the work for you for around $400 +/- depending on how complicated you design it.

Like I said, you are making new links, new pivots, modifying the body, mounting custom coilovers, etc. Why not just take a few extra steps and have a custom tank made and mount it behind the axle. Or hell, you could buy a generic rectangle tank and mount it behind the passenger seat or something like that if you really wanted to. Not to mention, you will probably save time on coilover mounts and stuff like that with the stock tank moved out of the way...

I will probably end up doing the F150 tank mod. It'll bolt in the same place you suggested and will give me room for the 4 link. Also, I read the writeup on it and i think he said they're only about $150 brand new from an auto parts shop.

 

[JBurt]

[MENTION=75445]4Running Daily[/MENTION] any thoughts?