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3spd auto 4wd to 5sp 4wd D/R ?? help?


Guest Razz600
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Guest Razz600

anyone done the conversion from an automatic 4WD to an 5spd 4wd D/R.

 

I was hoping someone would know how much shorter / or longer I need to make the rear drive shaft when doing this conversion So I can send it out while I am in process. Also, tranny mounts? any advice on that??

 

 

thanks...

 

 

Mark

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What car?

 

If its EA82, just go to the wrecking yard(the one in tigard should have one)and get a manual tranny driveline. While your at it, get the crossmember for a manual. The one for an auto serves as a rear crossmmember on a manual. not really necessary.

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Guest Razz600

Yes, I did plan ahead for the diff and the pedal box, I already have those...

 

I was considering putting in the 4wd 4speed D/R, but wanted the drive-ability of the 5speed 4wd D/R there for, the way I understand things the transmissions are different lenth and I would have to change the driveline in some fashion.

 

I do have a driveline from an 86 wagon.....I don't suppose that would work??? it has the carrier bearing though, and not sure off the top of my head where to put it......

 

Thanks all,

 

Mark

 

p.s. it's going into an 82 or 83 Brat (keeping the EA81), can't remember wich year it is right now..something I will have to get done in the next few weeks...I'm going to be moving soon.

 

mb

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There are tranny tunnel differences between the Auto and manual cars. You will have to make the hole bigger, and a different shape, and you will have to beat the hell out of the tranny tunnel, or cut into it, since it's not quite big enough around for the 5 spd. It can be done tho, fear not. So this is a Turbo BRAT your working on?

 

GD

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oh, you want a 5 speed D/R hooked up to an EA81?

you need the clutch disc (and TOB?) for the 5 speed tranny (the rest of the clutch stuff should be for an EA81 manual , you need the manual driveshaft shortened a certain amount (54mm?), and you should get Jerry to make you his mounting adapter kit. He has a one piece driveline instead of a modified two piece driveline on his car that i've seen this on.

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Guest Razz600

I already have the all the clutch parts I need from the 5speed and from the ea81 to make them match up...

 

I had forgotten about having to modify the tranny tunnel, but was planning on lifting the car at the same time since it was going to be pretty much disasembled anyway..was just going to flip the Rear Diff crossmember thingy, measure the difference, and raise the car up the same height it ended up being..

if I run short on time I also have an 4speed D/R and all the hardware to mount that up (4wd shift lever, etc)....I could do that and not worry about the lift at this point...

 

also, no it's not a Turbo...I wish...I do have an ea82 turbo, but was under the impression that the tranny / Engine Bell housings wouldn't match...would have to have an actual "Turbo Tranny" and replace the front CV's at the same time to match the Front splines..

 

Thanks,

 

Mark

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Guest Razz600

well,

 

after all the feedback, I'm considering sticking with the 4speed D/R in the Brat....anyone know if a rear drive shaft (between the tranny and diff) is the same lenth from an 84 wagon and a gen2 brat..??

 

mark

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Yeah - driveline is the same from a wagon. On the EA82T thing - no reason you can't use that - bell housings are the same, and will bolt to the 4 spd D/R, or the 5 spd D/R. VERY little room on either side of the engine tho - *maybe* 1/4". It's extremely tight. If you are lifting it, then the tranny tunnel won't be a problem probably, but the EA82T won't fit - with a lift, you will have to cut out the frame rails for it. You'll still need the manual tranny cross member tho. Maybe also the cross-member mounting plates too. I think those are different on the Auto's.

 

GD

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Guest Razz600

ok,

 

well since times a wasting, and so many things to do...here is the big plan.

 

I will pull the existing drive train (ea81, auto tranny, rear drive shaft, and rear diff), put a set of head gaskets on the ea81, replace the Auto tranny with 4spd D/R, and replace the rear diff with one from an 86 wagon that I have...(ratio's should match better)....and replace the rear drive shaft with that of the 84 wagon previously mentioned....I know that I have the tranny crossmember for the 4wd D/R in my "Pile-o-Parts", just have to locate it....

 

no lift, no ea82 drop in, just keeping it basically stock (well, I do hvae a weber in pieces, that I need to throw a rebuild kit in....that may find it's way into the Brat :) )...

 

Thanks all for the info, wish me luck. I will post when / if I ever get it completed..

 

mark

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Well lets see here.......

 

I am doing a 3AT to 88RX 5spd FT 4wd in my 83 Turbowagon.

 

Turbo gearboxes differ from non turbo(3.90) and auto usually shares the diff ratio of the turbo (3.70).

 

I am partway thru but under advisement of prior topics (please try search function in future it works great), and the USRM (we are working hard to get all the old stuff in and revised on the new site but I believe this is covered over there already), here is what I am doing.

 

I am getting the kit from Jerry.

I will use an ea82 clutch kit, I can use the xt6 (er27) clutch kit if I want to. I haven't bought either yet. Aftermarket parts sources tend to just have the kit be the same for both, dealer gets you a tougher clutch for the er27 xt6. You can use the full kit including throwout bearing, including the flywheel even if you want.

 

The Radius rod, plates and trans crossmembers are different between stick and auto along with the control arms.

 

The 5spd is supposed to be worth it especially if you live where theres a good change in elevation (hills/mtns, etc often) as you can be in a more optimal gear for the powerband more often.

 

The lift kit makes the space constraints easier as does Jerry's kit.

 

The driveshaft....you can use the ea82 one if you want to, Jerry recommends having the ea81 1 piece driveshaft LENGTHENED not shortened, to 54" long. That adds around 10 inches of driveshaft if I am not mistaken. I am going to have a shop do mine so its balanced, etc and I am probably going to provide another driveshaft for them to use to get the extra material from but who knows if they will use it. I may replace the u-joints at the same time to avoid future headaches if money isn't real tight.

 

Axle splines on a turbo ea82 trans are different than any of the ea81 trans models, and you have to use ea82 inner joints with ea81 outer joints or maybe you could shorten ea82 axles somehow I don't know whats the better route or if its possible.

 

I would say do what you have a nicer clutch kit for but without the lift kit, jerry's kit and a correct drive shaft it sounds like you might be better off with the 4spd dr trans.

 

Good luck!

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Guest Razz600

from what I have understood from the previous topics posted on the old board, if you purchase the CV shafts that would have come stock on Turbo Brat, the would match up with the spline of the newer transmission that your trying to match up to...somebody correct me if I'm wrong, but that's what i got out of the previous converstations

 

mark

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Guest Razz600

yes, it's very possible,

 

I have been trying to get all these facts that I learn into somewhat of a data base, but I do make errors.. Thanks for the info,

 

Mark

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  • 2 months later...
Guest Razz600

Well, it took longer than I thought to get to it, but now it's about finished..,.

 

 

I removed

the ea81 (with a blown head gasket)

3sp auto 4/wd tranny

 

replaced with

 

4speed D/R manual tranny

known good ea81 that I had laying around (but added a weber...heehheh)

 

things went pretty good, but like it was pointed out in the above posts, there are a few things to consider...

 

first...the gear ratio on the Auto's rear diff was the same as the one that I was going to replace it with...so I left the orriginal in place and kept the extra as that...an extra...

 

the Driveline fit in, but it was a little snug (between the rear of the tranny and the rear diff)...I made it work, but am going to be shortening it soon....it's started taking out the rear U-joint and causing some noise....also, I checked the length of the one that I was going to replace it with....out of an 84 4wd wagon, and it was the same length...exactly...so I kept the orrigianl

 

the tranny mounts.....well, this kicked me where it hurts...I thought I was all smart and all, and after yanking out the automatic and throwing all the extra parts in the junk heap (luckily in the back yard) I started dropping in the trann, bolted up with a standard crossmember....well, there arent mounting holse for the standard manual cross member in a brat that was set up for an auto...the auto DOES use a rear of the transmission mounted cross member...so back to the junk pile I wend and dug out all the mounts and the cross member...and bolted them to the existing holes on the manual tranny and in it went...no problem....mounted up and fitting nicely...

the shifter hole had to be delt with, but with a pair of tin snips and a rather large file, that was over come...I still have to mount the 4wd shift lever by the drivers seat.....a few minutes with the welder and that shouldn't be a problem...

 

probably the worst of them all was the pedal cluster under the dash....pain in the #$$ to pull out and replace...but that also was overcome...

 

the speedometer cable was to short, have to get another...but who needs to know how fast they are going anyway??

 

clutch cable...that was a breeze, just fit right in....no problem

 

something worthy of note...on the automatics, they have to be in park or N to start, when you drop a manual in, there isn't a way to tell where it is...there is no circuit for that...so, when I got frustrated because the ignition suddenly stopped working and threw some tools around, and the neighbor kid pointed out it wasn't in park, I felt like a fool.,.

 

anyway...that's the update...its at least running...,needs some improvements, but there is hope for it...

 

anyone know exactly how much to shorten the driveline? I'm thinging about 1/4 to 1/2 inch....any input

 

have a nice day...

 

mark

 

:banghead: :banghead:

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Was under the impression that the Wagon driveshaft was a direct swap-in on a BRAT. Guess not.

Best way I know of measuring for a driveshaft is to slide the front yoke into the tranny, stopping just as the brighter of the shinny part enters the seal. Now measure from the rear diff flange to the center of the u-joint cap on the yoke that's in the tranny. This is your over-all length.

Take the driveshaft and your measurement to the shop, tell them exactly how you determined the measurement. They should be able to do the shortening from that info.

I have had many driveshafts made over the years, and have used this method to get the length needed, be it a one, or two piece shaft.

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Guest Razz600

I was under that same impression also..

 

 

I was thinking of your same method, but wanted to check with the users on the board to see if someone else had knowedge on this..

 

Thanks for your input...

 

either way, it's been an educational project....

 

 

mark:D

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Not all autos have 3.7 gears (at least on EA82s, and I'm pretty sure it applies to EA81s too). I'm in the middle of a 5-speed D/R swap, since my '87 GL wagon had a bad automatic trans, but it also has 3.9 gears. So I didn't have to swap out rear-ends, but the front-end was pretty much shot on the '87, so I'm in the process of removing the strut/steering knuckle/axle/tie rod assemblies and replacing them with good parts from my '88 GL wagon (manual trans, blown engine).

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