720 Transmission rebuild kit??

[Zac7803]

Hey all, Just bought a 84 4x4 720 with a FS5W71B transmission in it. Which rebuild kit is going to work for this? I've read that 84 was a split year and it depends on the front countershaft bearing. Is there a way to tell before taking the transmission out and tearing apart? Any help is much appreciated.

[datzenmike]

I guess there is always a chance that the transmission was swapped but otherwise order by year. The '84 should have the 56mm countershaft bearing. The '85 and up 71B and 71C had the 62mm bearing. Nachi bearing from Japan are good. All 71Bs ceased to be used January '86 or half way through the model year and 71Cs used.

 

[Zac7803]

Thanks datzenmike! Where would be the best place to pick up the kit?

Quote

 

 

[datzenmike]

Looks like this will work but confirm.

 

https://www.transmissionpartsdistributors.com/fs5w71a-fs5w71c-transmission-rebuild-kit-with-synchro-rings-fits-77-84-datsun-nissan-200sx-280z-280zx-maxima-pickup-bk104ws/

 

[Zac7803]

@datzenmike thanks for the info. Found out my truck manufacture date was 9/83 so that kit you sent me should work. I guess the questions is now do i have to take the engine out to get transmission out or can I just drop the transmission?

[igotatruck]

4 hours ago, Zac7803 said:

@datzenmike thanks for the info. Found out my truck manufacture date was 9/83 so that kit you sent me should work. I guess the questions is now do i have to take the engine out to get transmission out or can I just drop the transmission?

Nah, you can drop it out without removing the engine. I pulled mine just with just a normal floor jack and a lot of cussing.

[igotatruck]

I ordered my bearings and rings from Midwest Transmission. Last I checked they sell replacement gears as well.

My thread: https://ratsun.net/topic/76171-transmission-rebuild-time

Edited December 15, 2020 by igotatruck

[bottomwatcher]

4x4 it is about even to pull engine with trans or drop out the bottom. Gotta move the 4x4 bits. I would pull the engine and trans out, they can be done together and putting them back together while out of the truck is easier. Also while the engine is out replace the front and rear seals along with any coolant hoses that are a bitch to replace with the engine installed. While out may as well clean and repaint. Glad you asked?

[datzenmike]

With difficulty you can drop it out from underneath. To lift out with the engine, add the following...

 

drain cooling system

remove rad... (good idea to remove water pump so plastic fan blades aren't broken while hoisting)

(if air con, the compressor has to come off and tied out of way. the condenser in front of rad may be ok)

disconnect battery

disconnect positive from starter and ground off the intake.

disconnect rusty exhaust down pipe

disconnect throttle cable

Disconnect carburetor wiring

disconnect distributor

disconnect alternator wiring.

disconnect engine harness (trans switches, start, oil sender, )

disconnect charcoal canister purge line

disconnect fuel and return lines

disconnect vacuum hoses to switches on passenger fender. (and ASCD if equipped)

disconnect heater hoses.

disconnect vacuum hose to brake booster.

disconnect engine mounts.

almost for sure I've missed something in this space.

 

Hoist and concrete floor to roll on with lots of head room. Advisable to have a load leveling device to tilt the engine up enough to lift out. Take lots of pictures so you get all wiring and hoses back to original place. Rusty exhaust studs/bolts can snap. 

 

Are you sure you want to undo all this to lift the engine out do nothing with it, and then put it back ?????  How is this saving time or work????

 

 

 

 

 

 

[bottomwatcher]

Have you dropped a trans out the bottom on a 4x4 Mike? I think I have done it 5 times and it sucks. If you have a lift maybe it's much better but on your back unbolting front driveshaft, front diff, cutting exhaust and wrestling it between the torsion bars is a bitch. Pulling the engine then slipping the trans out is probably a wash workwise but resealing the engine is easy. Any others out there experienced with the 4x4 removal festivities?

[datzenmike]

I was going to say no but it was a 4x4 tipped up on a 45 in a wrecking yard. No it wasn't easy. Still have it.

[matrophy]

If it helps, I am selling these for less than what they cost me - $40 including shipping

[620slodat]

Will these work for a 5sp on an SD-22 diesel? I think they will, but haven't done any checking yet. If they will work you can consider them sold. I'm only about 25 miles away from OSU (wife worked there for many years). We can continue this by PM to keep this forum uncluttered.

 

Don

[datzenmike]

'85 and '86 71Bs uses a 62mm counter bearing. If you have an SD22 it's got to be an earlier 71B with a 56mm counter bearing so the one for sale won't fit. You'll need to source a Nachi 56mm counter bearing.

[620slodat]

4 hours ago, datzenmike said:

'85 and '86 71Bs uses a 62mm counter bearing. If you have an SD22 it's got to be an earlier 71B with a 56mm counter bearing so the one for sale won't fit. You'll need to source a Nachi 56mm counter bearing.

 

This was just a back up, so if the larger bearing wasn't until 85 or later then this bearing won't fit. The transmission I have is an 81. Haven't had time to do any checking yet, planning to do so this evening. Too many irons in the fire for this afternoon.

 

Donj

[Charlie69]

Is it possible to machine for the larger bearing?

[datzenmike]

Absolutely.

 

 

Here's an '85 Diesel front case. The two bearings almost touch.

 

 

[620slodat]

19 hours ago, datzenmike said:

'85 and '86 71Bs uses a 62mm counter bearing. If you have an SD22 it's got to be an earlier 71B with a 56mm counter bearing so the one for sale won't fit. You'll need to source a Nachi 56mm counter bearing.

 

DM is correct. What I have found is the same as he stated. So, I will need a 56mm bearing for the countershaft. I don't need any bearings right away, but because of the time the transmission set without use I'm planning on replacing them sometime after getting them into use.

 

Don

[Charlie69]

Thank you Mike.

[matrophy]

On 1/3/2021 at 12:08 PM, 620slodat said:

Will these work for a 5sp on an SD-22 diesel? I think they will, but haven't done any checking yet. If they will work you can consider them sold. I'm only about 25 miles away from OSU (wife worked there for many years). We can continue this by PM to keep this forum uncluttered.

 

Don

Yeah - the countershaft bearing is 63mm. 

[620slodat]

I haven't taken the transmission apart to do any measuring, but from what  DM said, and what I could find, I will need a 56mm bearing. The gaskets would probably fit, but that bearing won't. So, unless you know somebody that can use a large bearing I will have to pass.

 

Don 

[datzenmike]

56mm was used in all 71B 4 and 5 speeds through '84. '85 and on and the later and newer 71C all used the 62mm counter. I have an '85 CA18ET 5 speed with an L series front case and put a new 56mm gear on. works very well. I took a 71B front case in to have it milled out and the guy said there was no one around that could do this work locally.

 

26 minutes ago, matrophy said:

Yeah - the countershaft bearing is 63mm. 

 

Make that 62mm.

 

 

 

[matrophy]

39 minutes ago, 620slodat said:

I haven't taken the transmission apart to do any measuring, but from what  DM said, and what I could find, I will need a 56mm bearing. The gaskets would probably fit, but that bearing won't. So, unless you know somebody that can use a large bearing I will have to pass.

 

Don 

No sweat. Thanks. I'm happy to keep the bearing and sell you the rest if that helps. No big deal either way. It's actually 62mm - responding to Mike's comment.

[frankendat]

I am interested in your stuff, but my transmission needs rebuilding. Do these parts come with a general transmission rebuild? Why would you need to sell these items, because your transmission needs rebuilt?

 

[Zac7803]

@datzenmike would a transmission out of a 82 work in an 84 that has a 71B in it currently? Are those years interchangeable?