Datsun Roadster Forum-311s.org

No, not LSD but a limited slip diff. Does anyone know how to tell what version a LSD is?

I've been told that there are two versions; one supports typical gearsets (4.11, 3.9 and 3.7) and the other really tall gearsets (4.38 and higher).

Can anyone confirm or support any of this? Thanks in advance! TR

Check out Gordon's website, lots of info and pics. http://www.gordon-glasgow.org/lsd5.asp If you already have a gear set in it, it will make it easier to figure out which you have. It looks like one type will take 3.70-4.11, 4.875-5.874, and the other will take 4.375, 4.625, 5.125 (But these could be used in the first type LSD if you have a spacer)

The LSD that came w/ my parts car has a 4.875 in it, my "Hopefully one day to be driven again Beast" has a 4.11, so I should be able to put the 4.11 gears in the LSD that came w/ the parts car. At least that is what I was told, never opened it to find out but have no reason to doubt previous owner as everything else he said was done, then some. That's the plan, but I need to get it up and runnning before I do anything else.

Unless someone out there wants to trade the LSD w/ 4.875 gears for a set of 68 or 69 NOS front fenders, I'd even toss in the rear sway bar that's on the car if it's going to be raced.

Never hurts to ask.

Hope this helps.

Happy Wrenching
Mark

Thanks for the reference. Am I missing where the info. on how to identify the version of LSD is? I don't see it...TR

If I'm reading Gordon's info right the LSD that takes the 3.70-4.11 and 4.875-5.874 is part # 38420-A9980, and the other LSD is part # 38420-16330. I'll crawl under the car this weekend and see if I have a part number stamped on my LSD (I think I do, center bottom)and post a pic.

Happy Wrenching
Mark

So the marking was on the carrier?

What if I only have the case assy?

TR

You will have to read the part numbers from the differential to tell which one you have. Mine had a 513 in it. When I took it apart there were shims under the ring gear. By just looking at the ratio you can't tell which type of differential it is. There is no way to tell without removing the pumpkin from the axle.

So, I am holding the clutch pack and spider gears and carrier (without the ring gear) in my hands. I do not have the original pumpkin, or diff housing. How do I tell which version it is?

I don't know. Are there no part numbers on any of the pieces? Gordon's site shows which part numbers belong in each type.

It has LDM52 10825 and PAT313151 on it...

I posted a pic in the general album...

TR

TR
Can you still get in touch w/ the previous owner, they might know? I really don't know much about the LSD's other that what I have read here and there.

Andy
I thought the 4.88 had alot of snap off of the line, I can't imagine what the 5.13 was like I put my tags on the parts car once I got the brakes and clutch bled and was grinning from ear to ear. Just had to drive it before I pulled the motor out.

I think that if you had a shim under your ring gear with the 5.13 you have the 38420-A9980 LSD.

Happy Wrenching
Mark

The 513 was pretty neat. There was never a corner where the appropriate gear couldn't be found. It made the powerband so wide that the motor never lugged. In addition to the 513 gears I had 20" tall tires which increased the ratio more. I was running autocrosses in second through fourth gears. I would be physically worn out at the end of an autocross run from all the shifting. I ended up building the U20 to the point that I broke the ring and pinion. It stripped a bunch of the teeth off. With the ubertorque if the KA I went with a 390. Now I don't have to shift out of 2nd until I get into the 60 mph range. It pulls through slow corners in second like a diesel truck. I still have the spacers for the ring gear. They are homemade out of galvanized steel sheets. I don't plan on going back with the higher ratio. After my forced induction ubertorque KA destroys the Nissan LSD I will probably switch out to a Ford 8.8 or a Winters. Maybe I ought to sell the LSD before I twist it into junk and use the money to buy the Winters. I'll probably sell the ring spacers also.

Sorry for the Hijack,

Later,