I have a 86 rx7 that does not have a LSD on it. I have a 89 GXL and was wondering if it does have the LSD on it. I do not see any stamps and I have looked all over the internet to see whether it came with an LSD but I keep finding different answers. The only thing on the casing is "M055 3" Any idea what that is?? Any help is appreciated.

 

Pop an axle out of the diff and check it out.

You see 4 spider gears, you've got an open.

Or better yet, jack the car off the ground. Grab a wheel and spin it. If they both dont move in the same direction, that's a good indication of what you have.

My GLX had an open diff, so did my se. The po of the gxl lied to me and told me it had a gtu lsd in it..... You could imagine how pissed off i was when i pulled a stub shaft out of the diff to inspect and saw it was open.


There may or may not be a "tag" on the drain plug that may or may not say "limited slip differential" You can remove the tag on the plug or swap lugs and given how old these cars are, serial numbers and tags aren't going to help you much in this area.

 

Put car in gear. Jack up rear (both rear tires off the ground). Turn one wheel by hand. If the other wheel spins in the opposite direction, it's an open diff (or your LSD is completely shot, and it's pretty much an open diff anyways at that point). If you cannot turn the wheel at all, put the gear in neutral and try again. If both wheels turn in the same direction when you turn one, it has LSD.

My LSD came from a GXL, and has M055 F (I think it's an F, kind of hard to tell) cast on it. No tag on the fill plug.

 

I don't think the stamp on the housing will tell you whether it's open or LSD, since the same housing is used for both - that's why the tag on the drainplug for LSDs, which of course may have come off or been removed and not put back for a fluid change at any point. Do the jacked - up test Nopistons! describes.

Even if your GXL had LSD, an '89 would have had a viscous, not the clutch-type S4's had, and after 21 years, it's likely it would behave much like an open diff - the silicone fluid that locks the diff under sheer forces sheers down itself over time. Although if the car hasn't been driven hard and is relatively low mileage, it may provide at least some LSD action.

 

S5 GXL's DONT has lsd.
S4 GXL's do.

It says it in the FAQ.

 

Oops, my bad, the viscous is only in S5 TII's. Your GXL is open, unless a previous owner swapped an S4 na LSD, FB GXL-SE, or Miata torsen in. Could be, but not likely. Check if you like anyway.

 

What would be the cheapest method of getting a lsd??? I know that my 91 does have the lsd but i want to get one for my brother in laws 86.

 

Get a S4 GXL LSD. You wont need the diff or axles. Orrrrrrr you could weld the open diff but i personally hate that crap.

 

I have a S4 GXL lsd for sale... going pretty cheap!

 

sorry but we have already bought 2 in the last 4 months so it is going to be a little while before we buy another lol

 

Ok. Now my next question is what would have to be welded to make this a LSD and how hard is it to weld????

 

Google would show you the answer no problem.

 

Welded isn't limited slip, it would locked up 24/7.

 

well still locked up is better than open lol