Info on EA81 gearbox conversion

RSR 555 · Post by **RSR 555** » Mon Aug 08, 2011 8:59 pm

Hey ppls, I'm looking for some info and help regarding gearbox conversion. Has anyone heard or seen someone use the rear transfer casing off a EA81 4spd 4WD box on a EA82 5spd 4WD box?

Gannon · Post by **Gannon** » Mon Aug 08, 2011 9:12 pm

Im think the design of the 2 boxes is different and not compatible.

Why do you want to?

YouTube · Post by **El_Freddo** » Tue Aug 09, 2011 12:48 am

I've not played around with this gearbox, but by the looks of it the rear housing seems to use the same bolting pattern at least - but I don't know what's different inside.

Why would you want to do this?? Or more to the point, what is it that you want to do??

Cheers

Bennie

Post by **TOONGA** » Tue Aug 09, 2011 8:38 am

the EA81 box is longer needing a shorter tailshaft (and the mounts are different?), if the rear of the box is able to be transplanted then the number of modifications needed to run a 5 speed L box would be less.

At least that was the gist of the conversation at sunset last Saturday

TOONGA

steptoe · Post by **steptoe** » Tue Aug 09, 2011 10:54 am

Paul must have someone that wants the sloppy shifter....with the vast difference of the shifter of forward and reverse of these two boxes, can't imagine it can be done.

Maybe just trying to build up post count

guyph_01 · Post by **guyph_01** » Tue Aug 09, 2011 11:19 am

I sense a Build for a very very special My:)

On my bro's Brumby the mods needed to fit the ea 5 speed to the EJ was,

-Shorten and re-welded gear links ( to keep factory MY cabin ones).
-Re-drilled My gearbox mount brackets to suit the bolt holes on the Ea82 gearbox.
-The use of My gearbox mounts bushes ($66ea from Subaru) that would bolt fairly straight onto the MY gearbox cross-member.
-Custom bracket to hold the Ea82 tail shaft to the body.

YouTube · Post by **El_Freddo** » Wed Aug 10, 2011 5:57 am

I'm intrigued as to what you're thinking with this one Paul. More details please

Cheers

Bennie

Post by **TOONGA** » Wed Aug 10, 2011 9:41 am

El_Freddo wrote:I'm intrigued as to what you're thinking with this one Paul. More details please

Cheers

Bennie

TOONGA wrote:the EA81 box is longer needing a shorter tailshaft (and the mounts are different?), if the rear of the box is able to be transplanted then the number of modifications needed to run a 5 speed L box would be less.

At least that was the gist of the conversation at sunset last Saturday

TOONGA

I wish I was joking when I wrote that post Bennie

TOONGA

YouTube · Post by **El_Freddo** » Wed Aug 10, 2011 5:23 pm

TOONGA wrote:the EA81 box is longer needing a shorter tailshaft (and the mounts are different?), if the rear of the box is able to be transplanted then the number of modifications needed to run a 5 speed L box would be less.

I've re-read what you've said and what I'm thinking you mean now is that you take an L series 5spd gearbox, remove the rear (stubby) L series housing with the 4wd engaging mechanism and replace it with the EA81 long rear housing to keep things stock in mountings etc.

That would be an interesting concept if it works - there might not be room for the 5 speed gears that are effectively "outside" the gear housing when looking at 1st/2nd etc.
The other thing I had a look at once while in the wrecking yard was the GLF-5 5 speed MY gearbox, I wonder if you can take this gearbox and convert it to a dual range MY 5 speed 4wd gearbox...

Either way there's a lot of stuffing around to find out if it works - if it does infact work then there are new options for those doing the 5 speed conversion - you'd still need the flywheel machined and the EA clutch setup and you'd still be stuck with that "dodgy" MY gear stick bush setup - I think the L series gear stick linkage setup was a vast improvement and a part of the appeal of the conversion...

More food for though

Cheers

Bennie

RSR 555 · Post by **RSR 555** » Thu Aug 11, 2011 8:23 pm

Thanks guys and sorry for the late reply but I'm only on the net with my mobile phone until my new home has the phone/internet connected.

Yes Bennie and Gannon, I'm pretty much looking to do as TOONGA has mentioned. I'm hoping to put the 5spd gearset inside the 4spd box, so I can use the 1 piece tailshaft, EA81 gearbox x-member, etc,etc

I was hoping someone had already looked into this and saved me the headaches

Jonno, I'm not sure the gear selection is much different but please explain some more as I have been wrong once or twice. I know the linkages are very different but they seem to follow the same selection action, if you know what I mean? And as for the post counts, I'm sure your average per day is a lot higher then mine :P

Yeah Guyph, I have converted many Brumbys and MY wagons to 5spd in my time, I've even used a MY 4spd gearset inside an EJ casing but that's another story. I'm hoping to do similar stuff/work that I did to the L.Series so most things underneath look factory.

steptoe · Post by **steptoe** » Thu Aug 11, 2011 9:05 pm

Sorry, my experiemce with MY boxes is horrific. Have pulled one apart and need a jigsaw to enlarge a hole to access the big nut at the back end of something. Almost like the socket to fit nut will never fit through hole as it stood. Bundled off to the scrap yard there.The dismantle of the rear end with all the shift ball stops - nightmare.
Some desparate farm boy welded the selector rail to the gearstick fitting making it impossible to renew the ever leaking seal, until I came along. I found a lump of weld banging into the seal nearly every shift

Shudder.....

RSR 555 · Post by **RSR 555** » Fri Aug 12, 2011 10:05 pm

Oh yes Jonno.. they are horrific but I've got the perfect way of fixing sloppy shifters on the MYs.

I should fix my last post as I meant to say I'm looking to use the EA82 gearbox front half and the EA81 rear half.

I'm going to have a play after I've got my other stuff sorted (that includes Dann and Guyph

)

Will report back with findings later.

YouTube · Post by **El_Freddo** » Sun Aug 14, 2011 11:47 pm

RSR 555 wrote: I should fix my last post as I meant to say I'm looking to use the EA82 gearbox front half and the EA81 rear half.

Ah yeah... This could be interesting. Not that I've seen the guts of an EA81 4 speed, but I reckon you might run into trouble with the gear on the end of the pinion shaft... One way to find out

Cheers

Bennie

guyph_01 · Post by **guyph_01** » Mon Aug 15, 2011 12:48 am

You can use the front half of my broken EA82 box if that helps. its only has some rear teeth missing and the low range is reserved for my EJ box:)

Do you need a EA82 or ea81 gearboxes to play with or you have them already? I might be able to get one of each unopened but unknown cond.... Let me know so i can check.

YouTube · Post by **El_Freddo** » Mon Aug 15, 2011 4:12 pm

Thinking about it you might be able to use the EA81's pinion shaft to make it all fit together...

I'm not keen to see how this all works...

Cheers

Bennie

RSR 555 · Post by **RSR 555** » Mon Aug 15, 2011 11:30 pm

More thoughts are need is my guess.. after thinking today

I tend to agree with Jonno and feel the gear selector shaft may be the issue. I think (haven't checked yet) that the angle and location of the selector shaft into the box may hold the key to this working (or in this case NOT!) but time and CSI work will come in due course

YouTube · Post by **El_Freddo** » Tue Aug 16, 2011 12:22 am

RSR 555 wrote:More thoughts are need is my guess.. after thinking today I tend to agree with Jonno and feel the gear selector shaft may be the issue. I think (haven't checked yet) that the angle and location of the selector shaft into the box may hold the key to this working (or in this case NOT!) but time and CSI work will come in due course

Paul, I strongly suggest that you get up in the morning and split an '81 box and an '82 box, lay them side by side and see what the differences are. About 2 seconds after this post a load of pics on here for us to digest.

My thoughts on this are (without having an '81 box split) that the gear selector should be fine, and if not will work ok with some modifications - 5th gear is just an extension to the gate that selects reverse, just that it moves in the opposite direction, so long as you can't select reverse after selecting 4th or 5th you should be sweet in the department.
The pinion shaft will have to be swapped for the '81's unit to match the rear housing, much like the FT4wd L series stuff works. Question will be if there's room in that rear housing to fit the 5th gear sets.
Of course you'll have to use the L series clutch etc with the shaved flywheel.
And you'll have to work out how to hook up the low range with a custom rod as the '81 box has the low range selection on the opposite side of the gearbox to the '82's...

If this works I know what I'll be doing with Sunnie the Brumby next

I've also wondered about the GLF-5 gearbox being used in a PT4wd DR gearbox to make a true EA81 Dual Range 4wd 5 speed gearbox... But I've not gone any further into this as I've not got a GLF-5 box to play with!

Cheers

Bennie