Builds Build #2 - 45 Extended Cab, 80 Frame, iForce 5.7 3UR

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Pretty funny comparison for anyone who hasn't seen a Tundra rear driveshaft... Toyota wasn't messing around!

Here it is compared to the 80 series rear driveshaft.
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Thanks! I'll be using the 6 speed behind the 3UR, as well as the Sequoia transfer case. Main issue right now is front axle orientation. Trying to figure out the path of least resistance to get the diff to the driver's side...
Remove knuckle balls and flop housing. Reinstall knuckle balls. Cut new ring gear reliefs in housing where diff mounts. May need to remove diff cover and rotate 180 degrees to work with ring gear. I am pretty sure this was done on Pirate 4x4 many years ago.
 
Thanks! I'll be using the 6 speed behind the 3UR, as well as the Sequoia transfer case. Main issue right now is front axle orientation. Trying to figure out the path of least resistance to get the diff to the driver's side...
That is going to be an awesome setup. Doesn’t Ruff Stuff or Diamond offer custom housings?
 
Remove knuckle balls and flop housing. Reinstall knuckle balls. Cut new ring gear reliefs in housing where diff mounts. May need to remove diff cover and rotate 180 degrees to work with ring gear. I am pretty sure this was done on Pirate 4x4 many years ago.
Im driving and dont want to die yet, so didnt read all way through the threads, but rustnailjustin flipped a front housing to pass drop on his 45 build. Couple threads:


 
Im driving and dont want to die yet, so didnt read all way through the threads, but rustnailjustin flipped a front housing to pass drop on his 45 build. Couple threads:


Thanks for the links! I agree, this is the easiest way. Unfortunately, I'm going to try and keep the factory 80 series suspension in tact, so it will take some careful cutting of the brackets so I can re use them. When I flip the axle and notch, cut and turn, I'll need to flip the coil spring perches, panhard mount, shock mounts, and like you mentioned, I'll have to cut the diff cover off and rotate it 180 degrees. Not the worst job, but definitely not easy.
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I took some measurements of the 3UR setup today after getting it back in the shop. These might be useful for someone in the future.
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From rear transfer case flange to front frank pulley is 70"

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Length of transmission and transfer case is about 46"

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Width of heads is about 33"

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Width of lower engine where it will fit between frame rails is 24"

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Height of front of engine, not including any oil pan is 26"
 
And a few other pictures

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Oil pan... It's actually pretty small and set back and to the passenger side

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Even if I rotated the transfer case for a passenger diff drop, the oil pan and heat exchanger on the transmission would be in the way.

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Plenty of room on the driver's side for a driveshaft

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Thanks for the links! I agree, this is the easiest way. Unfortunately, I'm going to try and keep the factory 80 series suspension in tact, so it will take some careful cutting of the brackets so I can re use them. When I flip the axle and notch, cut and turn, I'll need to flip the coil spring perches, panhard mount, shock mounts, and like you mentioned, I'll have to cut the diff cover off and rotate it 180 degrees. Not the worst job, but definitely not easy. View attachment 2795434View attachment 2795435
Couple comments/ideas:

I think factory brackets can all still be bought from toyota if its not worth the time trying to save the ones on your housing.

Id be curious if the housings are symmetrical about a vertical plane through the centerline of the axle shafts. If so, you could spin the housing 180 in the horizontal plane and remove the diff cover. Drill & tap new holes for mounting the diff housing. Knuckle balls can stay in. Spring perches can stay. Need to re do radius arm mounts and panhard mount. $1000 for a bare housing starts to sound really appealing...,
 
Couple comments/ideas:

I think factory brackets can all still be bought from toyota if its not worth the time trying to save the ones on your housing.

Id be curious if the housings are symmetrical about a vertical plane through the centerline of the axle shafts. If so, you could spin the housing 180 in the horizontal plane and remove the diff cover. Drill & tap new holes for mounting the diff housing. Knuckle balls can stay in. Spring perches can stay. Need to re do radius arm mounts and panhard mount. $1000 for a bare housing starts to sound really appealing...,
Awesome, I appreciate the input. I'll do some research.
 
Made some progress today, but definitely hit a bump in the road. Planned on taking the axle off, turning the balls 180 degrees, and cutting/remounting all brackets at 180 degrees also. The locking diff definitely has a non symmetrical bolt pattern and mounting face. I might have to cut the axle tube up and keep the orientation of the diff mount pointed up.

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Drill and retap new holes for the diff an option? Perhaps weld close the unused holes?
 
Drill and retap new holes for the diff an option? Perhaps weld close the unused holes?
I'm not too worried about the holes not lining up, more the lack of a flat surface on the opposite side of the notch where I'd basically need to duplicate it.
 
Vegas pic a part has a 92 FJ80 in it that had the full front axle last time I was there, if you needed something extra to work/ experiment with.
I saw a write up in a magazine where they cut down an axle housing and re-welded it together to change the overall width. They had jigs made up to hold everything straight.
Maybe you could cut the tubes off and switch sides, keeping the diff housing in the correct orientation.
 
I was able to grab an OEM gasket today at the dealer. There's pretty much nothing symmetrical about the front differential bolt circle. First pic is OEM gasket put on correctly. 2nd pic is OEM gasket flipped 180 degrees. Only 2 of the holes line up. 2 holes line halfway up, and the rest are a ways off. Pretty interesting...

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I was able to grab an OEM gasket today at the dealer. There's pretty much nothing symmetrical about the front differential bolt circle. First pic is OEM gasket put on correctly. 2nd pic is OEM gasket flipped 180 degrees. Only 2 of the holes line up. 2 holes line halfway up, and the rest are a ways off. Pretty interesting...

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That's a bugger, and at that, you don't know if you're rotating about the theoretical center of the diff housing. Time for a custom housing or time to get really crafty?
 
I did some surgery on the front axle. There is actually an outer mounting ring for the differential that's welded to the axle housing. My plan is to cut that off, and cut off the diff cover, then swap sides. Will also need to cut/turn the balls, and remount the spring pads and shock mounts.

Taking measurements first


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Cutting off mounts with plasma
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All clean
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Cutting off diff cover
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Cutting off diff flange
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