Another differential thread

[G8KeaPoR]

So I hate to admit it but I’m just not finding the answers I need in the search. 

 

Questions:

 

1. How do I figure out what rear end is mated to my 5speed trans and well what trans it even is.  I’m not seeing any plates on either and I’m not sure what side to start stripping that god awful just asking for rust rubberized undercoating that people still use for whatever reason. (Ok the god awful is my opinion and really to each their own I just hate caked on cars.)

2. If I find it isn’t an lsd unit what lsd should I buy and with what ratio. Or can it be converted?

3. Since it seems I can only find vlsd units does anyone have any experience converting it with say a Cusco clutch pack diff for the newer r160 housings and what would you recommend a 1.0, 1.5, or a way.  

 

Keep in in mind I have a CNC mill so making parts to make it fit isn’t an issue.  Also the car runs an l20b in it so I’d like some acceleration but I don’t want to be pegging the rpms at 70-75 on the freeway. 

 

 

[datzenmike]

I guess this is a 510? Unless replaced it will be a 3.90  R-165 differential.

 

Does the transmission have a bolt on oil pan on the bottom? If yes it's a 4 speed.

If reverse is above first you have an S10 dogleg 5 speed.

Low long is it from engine block to the start of the driveshaft? If 31.5" it's an FS5W71B. For a better ID you would have to post pictures.

 

Place in gear and raise both wheels off the ground and turn one.

If the other wheel turns in the opposite direction you don't have LSD

If you cannot turn it by hand and when placed in neutral both wheels turn in the same direction... probably you have LSD

[G8KeaPoR]

So I know it’s a 5 speed from driving it.  Supposedly it was pulled from a Z acccording to the previous owner and that I had an lsd unit but while the test indicated lsd when going around corners it gets a sound that in my Porsche transaxle days was and indication the clutchpack was about to go. Basically an abrasive gear whine.  Keep in mind Porsche’s used transaxle so there were obvious differences but I wanted to figure out if there was an identification stamping in order to either source parts or if I just need to buy a new insert.  Plus given its dog piss slow acceleration (my 81 kp61 starlet with 450k miles that originally had 55rwhp accelerated faster). I’m thinking I need to better mate the final drive to run on the l20b. Sorry I probably should have added in more info from the get go.  I will check the measurement of the trans once the hurricane passes.  We are pretty much just getting the rain portion but I have it parked in front of the garage with the 3500 beside it to act as a tree blocker ?

[G8KeaPoR]

23 hours ago, datzenmike said:

If reverse is above first you have an S10 dogleg 5 speed.

Low long is it from engine block to the start of the driveshaft? If 31.5" it's an FS5W71B. For a better ID you would have to post pictures.

 

To add it isn’t an I H pattern with first below reverse.  Reverse is below 5th.  There is not lift ring or anything either not sure if Datsun ever had those or not.

[datzenmike]

Both the 620 truck, the 280z and first year '79 280zx and the 810Maxima used the same 5 speed. Car transmissions had only the reverse switch on it, trucks had up to 3 other switches.

 

Well if you were to pull the rear cover off the gear ratio is stamped on the outer edge of the crown or ring gear. The rear cover may also have a foil label still stuck to it if a Subaru unit. Visually you could tell if LSD and what kind. The Subaru R160 had an LSD but I think it's a 4.11.

 

It might be from a 280 or 280zx but they are R-180 and didn't have LSD and neither did the R-200. Only the later 87 and up 300zx had R-200 LSD.

 

Also it might have some after market LSD in it.

 

Pray that it doesn't have an old Phantom Grip or Traction Concepts fake LSD in it

[yenpit]

What Mike said! ^^^^^^  There are some visual ques to help identify the Z/ZX 5speed gear ratio's.  A couple pictures from behind, of the tail housing & of the speedo pinion housing bolt location (12 oclock or 6 oclock) will help us identify.  Also, as Mike asked, what is the overall LENGTH of the trans?

 

By far the easiest thing to do on the rear end is pull the rear plate off.  Identifying as R160 vs R180 is tricky for those not experienced, as it comes down to the R160 being visually smaller than the R180.  You could potentially measure the spacing between the rear plate bolts, as they are spread further apart on the larger R180, let us know. 

 

For gear ratio, look for the stamped # on the edge of the ring gear.  For open vs LSD, look at the carrier......if you see four spider gears, it is open.  If you see a cast steel cylindrical unit instead, it should be an LSD.  Datsun Competition sold factory LSD R160's over the counter, never available in a USA production car.  Datsun Competition sold factory LSD R180's over the counter, never available in a USA production car.  Subaru offered the LSD R160 as a factory option on the turbo GL & RX series cars from around 1984-1989............these bolt right in to a 510 with the 510 inner stub axles.....bolt in!  Subaru offered the LSD R180's in the later WRX's etc, likely from around the early 2000's (WRX introduced here in the States 2002....??), but these units had snap rings on inner stub axles, so require the custom made 510 inner stub axles with snap rings.

 

Hope that helps!

 

TJ    

[G8KeaPoR]

Looks like I have my work cut out for me.  I will try and get to it this weekend if I get this job done on the mill. Couple of q’s.  I am assuming the cover just uses RTV or do I need some sort of hard to find gasket for the diff cover?  Also what diff fluid do you guys recommend?  For the trans I’ll snap some shots of it.  The speedo was never connected so I need to go under there anyway.  

[datzenmike]

Most gaskets are NLA now-a-days.

 

Try to get a proper sealer like Permatex #2...

 

 

This stuff sets up in 10 min and then join. It's thicker and I just feel more confident with it than that thin RTV stuff. I've used it on differentials several times before.

 

GL-5 gear oil in 80 w 90 weight. (do not top up your transmission with this stuff) There are some synthetics that are also good but they can slip past older seals.

[G-Duax]

You need to ID the LSD, as the Nissan Comp will be a clutch pack, or if a Subaru, it could be either a clutch pack, or a Torsen helical gear LSD.

A clutch pack style will require 'Anti-Chatter' additive if it seems to snap, crackle, and pop when going around a tight corner.

[yenpit]

Nissan still has all of the R160 & R180 differential gaskets, seals & orings.............easy to do!  Even if you have an earlier SUBBIE R160 or R180 clutch pack unit, same gaskets, seals & orings & cheaper from Nissan. 

 

I do NOT know if the later Subbie Torsen R180 units use the same gaskets, seals & orings...........

 

TJ

[G8KeaPoR]

Here’s a question if it isn’t could I just drop the 1500 on a Cusco clutch pack lsd for the pumpkin?

[G8KeaPoR]

On 10/22/2018 at 11:02 PM, datzenmike said:

Most gaskets are NLA now-a-days.

 

Try to get a proper sealer like Permatex #2...

 

 

This stuff sets up in 10 min and then join. It's thicker and I just feel more confident with it than that thin RTV stuff. I've used it on differentials several times before.

 

GL-5 gear oil in 80 w 90 weight. (do not top up your transmission with this stuff) There are some synthetics that are also good but they can slip past older seals.

If anything I can just use the rotary engine sealant I have. It’s night heat and in my experience if properly cleaned before application never leak.  I have cases on that in stock for the occasional rebuild on my 3rd gen rx7 and if not permeates has always been solid

 

[Josh K.]

Contact Troy Ermish if you want an aftermarket LSD. He knows what works/fits and how to assemble them correctly.

Edited December 22, 2018 by Josh K.

[datzenmike]

What about the Subaru H-160 LSDs???

[fivetenguy]

1 hour ago, G8KeaPoR said:

If anything I can just use the rotary engine sealant I have. It’s night heat and in my experience if properly cleaned before application never leak.  I have cases on that in stock for the occasional rebuild on my 3rd gen rx7 and if not permeates has always been solid

 

You can still get the diff cover gasket from a Subaru R160. Same with the three other oil seals. For the Subaru LSD's I just get the correct gear oil from Subaru.

[Josh K.]

I use Motul 90PA LSD Oil for my Subaru Clutch Packs.

[G8KeaPoR]

On 12/22/2018 at 9:51 PM, Josh K. said:

I use Motul 90PA LSD Oil for my Subaru Clutch Packs.

I’ve always been a motility fan when it came to motorcycles. And those were great for the wet clutch packs. I’ll give it a try.