Will 83 tranny work in an 85?

[GrettaGreen]

83 720 4wd tranny rebuilt 3 years ago for $60 on CL. Wondering if it would work on my 85?

 

Also curious if there are any tell tale signs that I should be aware of when I go look at it to see if it's worn.

[datzenmike]

Two things.

 

Length... some are 26" some are 31.5". The 4x4 tranny will have to be the same length as the one it's replacing

 

A 4X4 transmission will not have a speedometer drive in it. So if it's going into a 2wd you won't have a speedometer.

 

4X4 transmissions use a wider ratio gear set inside than a 2wd. First gear is slightly lower. (I guess that's three)

 

 

 

Well if you can drain it. The oil should be golden brown and clear see through. A light sulphur smell is normal. Run away if....white or milky fluid, as this indicates water dissolved in it, silver particles could be from the aluminum case. The drain bung is magnetic and a black paste on it is normal, it may have collected chips and chunks on it. If so just say no.

 

Magnetic drain bung with 'normal' black paste on it.

 

This is from a 720 diesel transmission I pulled apart. The piece on the magnet is...

 

...from the front counter bearing race.

[GrettaGreen]

It will be replacing a stock 4wd tranny.

 

Is there any way to tell if it is too worn to buy?

 

My current tranny makes a whining noise that seems louder than usual when I coast in gear, mostly in 1st, 2nd and 3rd. 4th and 5th is negligible. The PO said one of the plates was bent a bit and should be fine once it wears back to normal. It has been getting quieter the more I drive her. There has definitely been some tampering in the tranny that's for sure.

[GrettaGreen]

Yikes, that diesel plug looks gnarly.

 

Thanks for the tips!

 

Update soon.

[poor-mans-720]

since we are here on the subj. is there a difference between the Z22 and Z24 trans? I'm on my third starter, they keep blowing up. grinding teeth and destroying the drive end bushing. I replaced my flywheel from a Z22, but i dont know if my trans if from a Z22 as it has JY writing on it, so I am thinking the PO replaced it at some time. I think that since the flywheel is different sizes between the two, should the starter be clocked differently? and whats with the teeth count on the drive gear of the starter? on that i have has 8, but the other has 9. (Z22 with 4wd)

I am losing my mind over this...

[datzenmike]

The PO said one of the plates was bent a bit and should be fine once it wears back to normal. It has been getting quieter the more I drive her. There has definitely been some tampering in the tranny that's for sure.

 

I have no idea what he means but sounds fishy to me.

 

Usually the counter gear starts to whine. The good thing is that it is easy to get at and change but you have to take the transmission out. New gear and oil would likely cost less that a mystery 4x4 tranny... but no way to know for sure if this will fix it.

[datzenmike]

since we are here on the subj. is there a difference between the Z22 and Z24 trans? I'm on my third starter, they keep blowing up. grinding teeth and destroying the drive end bushing. I replaced my flywheel from a Z22, but i dont know if my trans if from a Z22 as it has JY writing on it, so I am thinking the PO replaced it at some time. I think that since the flywheel is different sizes between the two, should the starter be clocked differently? and whats with the teeth count on the drive gear of the starter? on that i have has 8, but the other has 9. (Z22 with 4wd)

I am losing my mind over this...

 

The flywheels 'size' refers to the diameter of the pressure plate that will fit on it. 200mm, 225mm or 240mm. (the bolt pattern for the PPs are different) They are physically the same otherwise ... other than some differences in weight. The starter rings are the same used from '68 through the '87 Pathfinder and Hardbody including the Z cars, Maxima, 200sx and used on all L and Z series motors.

 

If one has 9 teeth it must be a larger diameter than the 8 tooth one.

 

Look between the block and the transmission. There should be a thin plate sandwiched between them. Without it, the transmission (and the starter) will be positioned toward the rad about 1/16" and the starter would be that much further away from the flywheel starter ring.

[Sealik]

The 83 is probably 30.5"....but.....

Your 85 KC should be a 26".

 

You could swap your short to the longer trannie....but you would need the shorter propeller shaft and smaller companion flange for the T-case.

Also would need the longer console

 

Always good to have extra 720s lying about :D

[poor-mans-720]

Okay, that makes sense. Can i change the starter rings? RockAuto sells them, but i cant imagine its easy to change.

okay, I will try the 9 tooth starter, It is the one that was matched to the flywheel that i got from the JY.

I do have the flex plate in there. I guess replacing the flywheel and starter again is my only option. just getting tired of replacing it every two months.

DatzenMike... your Datsun-pedia!!!

[datzenmike]

Yes the starter ring can be changed. Carefully cut the ring with an angle grinder and slip it off. Try not to nick the flywheel.

 

Put the flywheel in the freezer over night. The next morning heat the starter ring in the oven set at 375F. Assemble quickly and tap into place.

[poor-mans-720]

nice... I know what i am doing tomorrow.