Reversing Rotation of Toy axles.

[zerobalance]

I posted this up in newb and haven't figured it out yet, and I've spent a few days on google and chasing crap dead links.

Flipped Diff Rear Engine Questions

I am selling the rubi 44s I reference in that thread, and I think it's better to build a pair of 8" yota axles I have.

I am planning to swap the ends around around with custom shafts to get a centered front diff and offset rear diff. The vehicle they are going in is rear engine, with the transmission and t case in front of the engine.

Since I'm building both axles, I can manipulate center section and diff in any way needed. I also have no problem doing needed machine work to hopefully keep them oiled.

Can I get away with just flipping the diffs over and changing the cover to match the ring gear. I see a lot about running on the coast side of the gear being weaker, but haven't really found much about anyone actually blowing one up.

 

[the_white_shadow]

Most toyota 8" axles (if not all) do not have a cover up front to remove and/or flip. Lots and lots of guys use 8" toyota diffs flipped in their portal cars. No issues with oiling or running on the coast side of the ring gears, but they are on portals.

What engine and tires are you planning on running? Not sure id use a toyota 3rd, but instead 9" 3rd member.

 

[YotaAtieToo]

I posted this up in newb and haven't figured it out yet, and I've spent a few days on google and chasing crap dead links.

Flipped Diff Rear Engine Questions

I am selling the rubi 44s I reference in that thread, and I think it's better to build a pair of 8" yota axles I have.

I am planning to swap the ends around around with custom shafts to get a centered front diff and offset rear diff. The vehicle they are going in is rear engine, with the transmission and t case in front of the engine.

Since I'm building both axles, I can manipulate center section and diff in any way needed. I also have no problem doing needed machine work to hopefully keep them oiled.

Can I get away with just flipping the diffs over and changing the cover to match the ring gear. I see a lot about running on the coast side of the gear being weaker, but haven't really found much about anyone actually blowing one up.

Biggest concern I would have would be oiling in the rear with a flipped 3rd. Imo, it would be worth it to get a hold of an FJ80 HP 3rd to use in the rear (upside down, low pinion)

It's definitely possible to build them yourself. Basically use the scented rear houong in the front, with steering knuckles welded on, then the front housing in the rear with either the stock housing ends spliced on, or a flange to run a spindle for full float.

You wouldn't flip the cover, you'd flip the whole housing.

Like I mentioned in the other thread, Toyota axles have lots of support, so ordering a set of housing with the correct shafts would definitely be possible diamond.

 

[Aisin]

I flipped my FZJ80 rear axle. I cut the cover off m, spun it 180 and hot glued it back on. I had to cut 2 notches in the face of the housing for the ring gear.

 

[Slander]

I flipped my FZJ80 rear axle. I cut the cover off m, spun it 180 and hot glued it back on. I had to cut 2 notches in the face of the housing for the ring gear.

He's talking about flipping the LP third to HP with a rear engine

 

[Aisin]

He's talking about flipping the LP third to HP with a rear engine

Ahhh. I have been drinking a lot lately. Depression is a mother fucker sometimes.

 

[Slander]

Ahhh. I have been drinking a lot lately. Depression is a mother fucker sometimes.

Sucks man, get that truck done and go wheel!!!

 

[Aisin]

Sucks man, get that truck done and go wheel!!!

That’s the plan. Our hottest month is over here finally. Just need to make two new hard lines for the rear brakes. Turns out my flare tool kit is the wrong one.

 

[zerobalance]

Most toyota 8" axles (if not all) do not have a cover up front to remove and/or flip. Lots and lots of guys use 8" toyota diffs flipped in their portal cars. No issues with oiling or running on the coast side of the ring gears, but they are on portals.

What engine and tires are you planning on running? Not sure id use a toyota 3rd, but instead 9" 3rd member.

I meant cut the cover off and reweld it flipped. Portals wouldn't really change oiling or gear mesh characteristics would they? Using a VW TDI mated to a nv3550 and np24j out of a TJ rubicon. will never be on bigger than a 31" tire. Id like to stick with Yota or d44 axles just for simplicity, and easy availability of custom shafts.

Biggest concern I would have would be oiling in the rear with a flipped 3rd. Imo, it would be worth it to get a hold of an FJ80 HP 3rd to use in the rear (upside down, low pinion)

It's definitely possible to build them yourself. Basically use the scented rear houong in the front, with steering knuckles welded on, then the front housing in the rear with either the stock housing ends spliced on, or a flange to run a spindle for full float.

You wouldn't flip the cover, you'd flip the whole housing.

Like I mentioned in the other thread, Toyota axles have lots of support, so ordering a set of housing with the correct shafts would definitely be possible diamond.

Oiling is a concern, I'm sure there are ways around that. I considered fabricating my own housings, I have a plasma table and press brake, but project creep is always a concern. I also would like to keep the budget under control. Aside from just sticking them under samurais in the past, I really don't know shit about toyota axles. I am a very visual person, any sometimes have trouble wrapping my head around stuff without drawing it or just trying it, I might sling an axle under the bus today and see if it greases the wheels.

 

[the_white_shadow]

I meant cut the cover off and reweld it flipped. Portals wouldn't really change oiling or gear mesh characteristics would they? Using a VW TDI mated to a nv3550 and np24j out of a TJ rubicon. will never be on bigger than a 31" tire. Id like to stick with Yota or d44 axles just for simplicity, and easy availability of custom shafts.

Oiling is a concern, I'm sure there are ways around that. I considered fabricating my own housings, I have a plasma table and press brake, but project creep is always a concern. I also would like to keep the budget under control. Aside from just sticking them under samurais in the past, I really don't know shit about toyota axles. I am a very visual person, any sometimes have trouble wrapping my head around stuff without drawing it or just trying it, I might sling an axle under the bus today and see if it greases the wheels.

Portals require you to flip the thirds for reverse rotation. Thats it. So they would be in the same orientation as with what you are trying to do, just without the rear engine. To be honest with you, id just buy a set of trail gear housing from summit vs building them, unless you just really really love to do that kind of stuff. As said previously, you can flip the entire stock housing and cut off the bells to make it work for what youre trying to accomplish. Only issue with that is you lose a little ground clearance with the factory truss now on the bottom. You can always cut that off though. Drain/fill plugs are now flipped as well.

 

[YotaAtieToo]

Portals require you to flip the thirds for reverse rotation. Thats it. So they would be in the same orientation as with what you are trying to do, just without the rear engine. To be honest with you, id just buy a set of trail gear housing from summit vs building them, unless you just really really love to do that kind of stuff. As said previously, you can flip the entire stock housing and cut off the bells to make it work for what youre trying to accomplish. Only issue with that is you lose a little ground clearance with the factory truss now on the bottom. You can always cut that off though. Drain/fill plugs are now flipped as well.

Buying trail gear housings would be a waste of time and money. They don't make a centered steering axle, or a drastically offset rear. Not to mention they're not upside down

Actually, I'm just remebering that they started making fab'd housings with no ends on them like diamond and ruff stuff.

 

[the_white_shadow]

Buying trail gear housings would be a waste of time and money. They don't make a centered steering axle, or a drastically offset rear. Not to mention they're not upside down

Actually, I'm just remebering that they started making fab'd housings with no ends on them like diamond and ruff stuff.

Yep, they make fabricated housings that arent the rock assault ugly ones. You can flip them anyways you want with plenty of tube to offset them in any direction.

 

[YotaAtieToo]

Yep, they make fabricated housings that arent the rock assault ugly ones. You can flip them anyways you want with plenty of tube to offset them in any direction.

Do they have a 3" tube option? 3.5"x375 would be pretty overkill for 100hp and 31s

 

[the_white_shadow]

Do they have a 3" tube option? 3.5"x375 would be pretty overkill for 100hp and 31s

Yep

 

[Poopyota]

It sounds like you have the rear engine thing all figured out. My buddy has a solid axle rear engine 4400 car and all it is, is the drivetrain in the car backwards with LP 9”s in flipped housings with a center front diff and offset rear diff. If you end up building axles Toyota axles they are tough for what they are but they are pricey in comparison to a lot of other options. If you go the fabbed housing route you could probably get built 9” diffs from summit cheaper than you could build 8” Toys. Plus the steering angle for the Toyota closed knuckle leaves a lot to be desired. I have wheeled Toy axles for a long time Plus they are more difficult to work on. A cheap alternative for outers is the Dana 50. In stock form they are worthless but they have the same outer as a Dana 60 of the same year. You just cut off the outers and machine the inner C’s to fit your housing

 

[YotaAtieToo]

It sounds like you have the rear engine thing all figured out. My buddy has a solid axle rear engine 4400 car and all it is, is the drivetrain in the car backwards with LP 9”s in flipped housings with a center front diff and offset rear diff. If you end up building axles Toyota axles they are tough for what they are but they are pricey in comparison to a lot of other options. If you go the fabbed housing route you could probably get built 9” diffs from summit cheaper than you could build 8” Toys. Plus the steering angle for the Toyota closed knuckle leaves a lot to be desired. I have wheeled Toy axles for a long time Plus they are more difficult to work on. A cheap alternative for outers is the Dana 50. In stock form they are worthless but they have the same outer as a Dana 60 of the same year. You just cut off the outers and machine the inner C’s to fit your housing

Find his build thread, it's literally a VW bus with a 100hp tdi on 30" tires.

I agree with what you're saying, about building a 9" vs Toyota, but he does already have the Toyotas. So he wouldn't need to source outters for the front, or 3rds.

Also, a Toyota HP is a fuck ton cheaper than a HP 9" 3rd

 

[Poopyota]

Find his build thread, it's literally a VW bus with a 100hp tdi on 30" tires.

I agree with what you're saying, about building a 9" vs Toyota, but he does already have the Toyotas. So he wouldn't need to source outters for the front, or 3rds.

Also, a Toyota HP is a fuck ton cheaper than a HP 9" 3rd

I didn’t look at what he was building You don’t need high pinions when you’re running your differentials upside down, your low pinions become high pinions. Just a quick Google search comes up with a lot of 9 inch third members that are complete for less than what you can get a built third member for from Marlin Crawler. But the problem that he’s going to run into is he’s going to have to get custom axle shafts made to make all that Toyota stuff work. I don’t know for sure but a lot of times when you get custom axles made the manufacturers have blanks that they machine from. Dana 60 stuff is really common blanks whereas I don’t know if they have Toyota blanks to make 30 spline stuff out of. I guess the OP will find out. Maybe if this works out, the OP could have stock semi float rear axles cut and splined on the other end to work as the fronts since the inner axles will lose length because of the outers, and then in the rear maybe he could cut one of the semi floats for the offset diff on the short side and get it resplined then maybe he only has to get one custom axle made? Maybe if he goes into the build thinking that way he could save himself some money with his measurements on the axle widths?

 

[Poopyota]

It looks like a stock rear necks down to the splines there could be enough meat for resplining. It looks pretty affordable through Branik

 

[YotaAtieToo]

I didn’t look at what he was building You don’t need high pinions when you’re running your differentials upside down, your low pinions become high pinions. Just a quick Google search comes up with a lot of 9 inch third members that are complete for less than what you can get a built third member for from Marlin Crawler. But the problem that he’s going to run into is he’s going to have to get custom axle shafts made to make all that Toyota stuff work. I don’t know for sure but a lot of times when you get custom axles made the manufacturers have blanks that they machine from. Dana 60 stuff is really common blanks whereas I don’t know if they have Toyota blanks to make 30 spline stuff out of. I guess the OP will find out. Maybe if this works out, the OP could have stock semi float rear axles cut and splined on the other end to work as the fronts since the inner axles will lose length because of the outers, and then in the rear maybe he could cut one of the semi floats for the offset diff on the short side and get it resplined then maybe he only has to get one custom axle made? Maybe if he goes into the build thinking that way he could save himself some money with his measurements on the axle widths?

Maybe you should read more...

No shit I get that a low pinion becomes a high pinion when it's upside down

The problem is that when you do that, the rear is now not only running on the coast side, but it's not meant to be a high pinion and starving the pinion bearings on the highway is very likely. Obviously this isn't an issue with moon buggies and I'm sure U4 guys have it figured out with the 9"

So in short, the easy solution for something like op is a high pinion.

Custom length axles are definitely available for the front. I don't even think it's extra when buying rcv's. The rear, you may have a point if the diff needs to be way offset. Trail gear makes a Toyota rear for a samurai, but it's not near as offset as a front axle.

A t100 or tundra axle shaft for the long side might just be enough, then a cut down one for the other?

That's another reason why I mentioned a full float rear. They're just double spline, so easy peasy. Then you get the same spindles, hubs, ect f&r.

 

[Poopyota]

Maybe you should read more...

No shit I get that a low pinion becomes a high pinion when it's upside down

The problem is that when you do that, the rear is now not only running on the coast side, but it's not meant to be a high pinion and starving the pinion bearings on the highway is very likely. Obviously this isn't an issue with moon buggies and I'm sure U4 guys have it figured out with the 9"

So in short, the easy solution for something like op is a high pinion.

Custom length axles aren't terrible, but you're probably right, it might be cheaper for a 9"

I thought it was 100hp and we weren’t worried about strength a lot of Toyota’s are out there running low pinions in the front getting beat on with big tires riding on the coast side of the gear The hypoid offset of a 9” and toy are drastically different. I bet if you over fill the oil that LP Toy upside down it won’t care. U4 cars with 9”(10”) aren’t slinging oil in those fabbed housings they are just over filled with 250wt race oil. They do get rebuilt frequently though I’ll give you that

 

[YotaAtieToo]

It's not strength, it's running down the highway with the pinion bearings not getting oil.

Maybe it will work, maybe it won't. But when a new 3rd is $450, and all the guts cost the same, I think it's worth it to not be stranded in bfe.

 

[Poopyota]

It's not strength, it's running down the highway with the pinion bearings not getting oil.

Maybe it will work, maybe it won't. But when a new 3rd is $450, and all the guts cost the same, I think it's worth it to not be stranded in bfe.

I get what you are saying that’s the right way to do it. I thought he was trying build these axles out of what he has. I don’t know the OP’s budget and I haven’t even seen his thread clearly I don’t know what he is trying to do

 

[YotaAtieToo]

Also, overfilling is pretty detrimental in all ways. Prevents proper slinging, and in my experience just blows out the breather anyway.

Not saying you're wrong, because it sounds like the HP 9 fill plugs are higher than the lp. Just not sure if you can apply the same to an old Toyota 3rd and have the same success. Not to mention 250wt isn't realistic for anything that's not racing. Remember a few years ago when it was cold at koh and everyone had to preheat thier diffs before they raced because the oil was so thick it would just act like gel and the diff would blow before it warmed up fully if they went straight to racing?

If he's wanting to try the flipped low pinion. I'd definitely add this, it's too cheap not to.