Hi
I am only new to this site and to the mx5 scene, so i hope I'm posting this in the right spot.
I have a nb8b 6 speed, and have just bought a 4.1 torsen diff without any housing for it, i was told that i could just unscrew the bolts from the housing on my car take out the original diff (while still connected to the car) and then install the torsen diff and bolt it back up and I'm done. what I'm actually asking is it really a DIY job, or should i take it the shop to get done, and if it is a DIY, could anyone give me any links so i can see the process of it, or help me themselves
Thanks
Help Please how to install a torsen diff into standard housing
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Re: Help Please how to install a torsen diff into standard housing
It can be diy, but only.If you have dial gauges and know how to set backlash.
Set the lash wrong and you'll destroy the diff.
Also you really should use a crown and pinion from the same car, as they bed into one another over time.
Removing the pinion requires a press, and you should put fresh bearings and seals in while it's all apart.
Basically, unless you've done it before, take it to a shop.
Set the lash wrong and you'll destroy the diff.
Also you really should use a crown and pinion from the same car, as they bed into one another over time.
Removing the pinion requires a press, and you should put fresh bearings and seals in while it's all apart.
Basically, unless you've done it before, take it to a shop.
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Re: Help Please how to install a torsen diff into standard housing
This is eminently DIY, this old fart just did a solo remove and replace (of the complete unit) with the car on jack stands and a trolley jack. The alloy housing is just that, the 'pineapple' simply bolts in, job done. New seals at the axle ends of course.
It requires removal of the axles; removal of the propshaft, and removal of the PPF. The only tricky bit is removal of one of the long bolts holding the PPF to the diff nose, and that can be a bastard of a job if the sleeve on this bolt is corroded in place. I use a dynabolt to pull it down. It can be simpler to remove the diff and PPF as a unit and separate them on the garage floor if that sleeve proves stubborn.
Search on here and the big board (miatanet.com) garage section, there is bound to be findable tips and tricks around.
If you are confident the diff has been put together competently, you should have no problems with DIY. Did it come out of a running car? If so, and bought form a reputable seller, you should be good to go.

On preview, my comments are based on the installation of a pre-assembled CWP/torsen unit. If you have to assemble the CWP to the torsen, I would have the experts do this. It is doable as DIY, but it wouldn't be something I would try, and I do a lot of DIY mechanicing.
It requires removal of the axles; removal of the propshaft, and removal of the PPF. The only tricky bit is removal of one of the long bolts holding the PPF to the diff nose, and that can be a bastard of a job if the sleeve on this bolt is corroded in place. I use a dynabolt to pull it down. It can be simpler to remove the diff and PPF as a unit and separate them on the garage floor if that sleeve proves stubborn.
Search on here and the big board (miatanet.com) garage section, there is bound to be findable tips and tricks around.
If you are confident the diff has been put together competently, you should have no problems with DIY. Did it come out of a running car? If so, and bought form a reputable seller, you should be good to go.

On preview, my comments are based on the installation of a pre-assembled CWP/torsen unit. If you have to assemble the CWP to the torsen, I would have the experts do this. It is doable as DIY, but it wouldn't be something I would try, and I do a lot of DIY mechanicing.
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Re: Help Please how to install a torsen diff into standard housing
Thanks heaps for your help, I think after reading your comments I will leave it with the mechanic next time I go to get some work done
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Re: Help Please how to install a torsen diff into standard housing
If its the diff centre only, even your mechanic will probably give it to a specialist and install the housing himself afterwards.
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Re: Help Please how to install a torsen diff into standard housing
If it's just bolting a complete diff into the carrier housing then any competent mechanic can do it, including good home mechanics. If it's replacing an open centre with a torsen centre in an existing diff then you need a specialised transmission shop. They should replace all seals and at least check all bearings at the same time.
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Re: Help Please how to install a torsen diff into standard housing
These guys are thinking you are using just the gears. It is a complete assembly that just bolts in. No special tools are required. You just unbolt the pumpkin, and bolt the new one.
NA8B - P.I 1:50.1 Wntn1:38.0 Sand1:27.6 Wntn S1:08 Bfrd1:06.9 Cldr1:08.5 Wak1:10.4
"SE" - P.I 1:43.8 Wntn1:32.9 Sand1:22.0 Bfrd1:05.3
"SE" - P.I 1:43.8 Wntn1:32.9 Sand1:22.0 Bfrd1:05.3
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Re: Help Please how to install a torsen diff into standard housing
it really depends on what you have.
If what you have looks like this:

Then DIY is relatively easy, being essentially an unbolt your old one, shove in the new one. (meaning the whole nose, dont touch the bits inside)
If what you have is this:

then you are best to take it to a shop and have them set it all up correctly so it doesnt chew itself apart.
If what you have looks like this:

Then DIY is relatively easy, being essentially an unbolt your old one, shove in the new one. (meaning the whole nose, dont touch the bits inside)
If what you have is this:

then you are best to take it to a shop and have them set it all up correctly so it doesnt chew itself apart.
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Re: Help Please how to install a torsen diff into standard housing
Hi thanks for all your replies, the diff is from lightyear, so it is what he said, whole diff going into the housing, thanks hks for the picture uploads so i could see, it does look easy enough for me to do, i think ill be able to do this one myself, again thanks everyone for your help
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