GVR-4: 3 bolt LSD how strong?

blkchr91 · 08-02-2012, 10:16 AM

Just wondering how strong (ehh weak) the 3 bolt LSD is. Not a big fan of change here and like to work with what I have.

I put some heavyweight shockproof in it to try to make it last longer.

Also, how do they usually die and how can they die? Will I be able to get home?

Thanks

black_gst · 08-02-2012, 10:17 AM

Quote:

Originally Posted by blkchr91

Just wondering how strong (ehh weak) the 3 bolt LSD is. Not a big fan of change here and like to work with what I have.

I put some heavyweight shockproof in it to try to make it last longer.

Also, how do they usually die and how can they die? Will I be able to get home?

Thanks

its 25% weaker then a 4 bolt

and the fluid you run has nothing to do with how strong it is... do you even know the difference between the two?

blkchr91 · 08-02-2012, 10:26 AM

That is a good statistic. I am surprised that my choice in fluid has nothing to do with the strength (definition of strength to me is partially at least how long it might last me).

The difference between the 2 is easily searchable and I have read it but I had no interest in the technicalities. I am concerned only with the outcome.

Also, still looking for how they generally fail and if I would be able to get home under most circumstances.

Quote:

Originally Posted by black_gst

its 25% weaker then a 4 bolt

and the fluid you run has nothing to do with how strong it is... do you even know the difference between the two?

urbansmoker1 · 08-02-2012, 10:31 AM

id assume that when your rear diff goes you would be limping on FWD home. Although depending on HOW it breaks could determind weather you can go anywhere. im sure the whole damn thing could explode and leave your rear axels on the track. or you could just sheer the gears and still be able to roll around with half your drive train working. It all depends on how bad it is. if it was me, and i broke anything, i wouldn't be trying to drive it period. let alone home; It would be on a flatbed.

And_44 · 08-02-2012, 10:32 AM

Depends on your goals for power if it will hold up to it or not. But they are decent. I'd worry about it myself if I was approaching 500whp. As for the LSD if your not having any issues with it now and put some redline heavy shock in it that's a good step to some good protection and maintence.

Fluid isn't going to make it stronger. But just make it deal with the stress easier.

They usually die from to much torque being put through it

black_gst · 08-02-2012, 10:33 AM

Quote:

Originally Posted by blkchr91

That is a good statistic. I am surprised that my choice in fluid has nothing to do with the strength (definition of strength to me is partially at least how long it might last me).

longevity would be the word your searching for, not strength

Quote:

Originally Posted by blkchr91

The difference between the 2 is easily searchable and I have read it but I had no interest in the technicalities.

so search it, one has three bolts to bolt the diff to the axles the other has 4 bolts

Quote:

Originally Posted by blkchr91

I am concerned only with the outcome.

search that too

Quote:

Originally Posted by blkchr91

Also, still looking for how they generally fail and if I would be able to get home under most circumstances.

they break, and DSM's always look pretty on a flatbed

if you put as much effort into searching as you do typing question to get around searching for youself you would have found the answers you looking for

blkchr91 · 08-02-2012, 10:37 AM

Thanks for all relevant and useful data contained within the posts everyone. I know how to proceed now. I will not be deterred from asking questions by comments that directly imply or have a nexus to being required to search to find the answer which is contrary to the terms of service contained within the terms of service at it pertains to this section of the board.

For the record, this post is on topic and not disruptive because it became part of the topic when black_gst made it part of the topic.

I have nothing further to say about using the "search" functionality of this forum within this thread.

ramsack · 08-02-2012, 10:39 AM

I don't think your choice in fluid will affect a stock LSD in ANY way. They're sealed units with their own silicone-based oil. On a side note, how are these things lasting this long? Surely there's going to come a time where the viscous couplings and diffs just stop working and Mitsubishi is going to just say "too bad!"

GRAVEDIGGER · 08-02-2012, 11:10 AM

I twisted my passenger side 3-bolt axle off right where the splines go into the rear differential, so that the spline end of the axle shaft was stuck in the rear diff. I believe this is where most of them break too. I was at the track, so I just unbolted and pulled the axle out, stuffed a piece of rag in the hole where the axle went, and drove it home.

jtmcinder · 08-02-2012, 11:16 AM

Is the question about the strength of the LSD or is the question about the strength of the diff?

blkchr91 · 08-02-2012, 11:21 AM

Thanks for the thoughts everyone. Guess I should carry a rag around!

The question really was intended to be more along the lines of the strength of the diff, but I never stopped to think about the LSD and diff being different entities.

I guess moving forward, it is a question about both.

SonySlave · 08-02-2012, 11:21 AM

The diff itself, as in the ring and pinion, and the LSD are pretty darn strong and will very unlikely break unless you wheel hop the rear tires really bad. It's the thin 3-bolt rear axles that could be your issue. The 3-bolt axles don't hold up very well to higher horsepower launches. That would be my only concern.

jtmcinder · 08-02-2012, 11:28 AM

Quote:

Originally Posted by blkchr91

The question really was intended to be more along the lines of the strength of the diff, but I never stopped to think about the LSD and diff being different entities.

The OE LSDs in a DSM are piggy-back VCs, so they are completely separate from the actual diff. In contrast, a popular upgrade for the rear of a DSM (for drag-racing, especially) is to swap in a modified clutch-pack, where the LSD is part of the diff, itself. Likewise, when you upgrade the front in an AWD, you often swap in a helical, where, again, the LSD is part of the diff, itself.

Background: Diffs & LSDs - Part 1 - Types of Differentials and Diffs & LSDs - Part 2 - Types of Limited Slip

blkchr91 · 08-02-2012, 11:51 AM

Thank you very much everyone. I certainly have enough to go on.

ZeGaNe69 · 03-03-2013, 07:01 AM

Hi guys.

I have researched the forums, but still have not found the right answer to my question.
I have 3-bolt rear end with LSD, thinking about 4-bolt swap, but it is so hard to get in Europe.

My question: are 3-bolt and 4-bolt axle bars interchangeable?? I have measured and counted 3-bolt bar`s splines and outer diameter.

Both sides (ends) have 22 outer splines and diameter is 24mm (from spline area).
Forgot to measure the bar`s length.

Thanks.