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slkspd
09-09-2007, 11:57 PM
I broke the half shaft on the first test run.
is there any way to use my alltrack tranny?
is it possible to make it front or rear wheel
only? if not, what do i need to make my 90'
GT an alltrack?

Ricksta
09-10-2007, 12:02 AM
you can use an mr2 tranny and use mr2 inner and alltrac outer shafts. theres a guy who made his alltrac a v8 rwd not sure how he did it. cant use an alltrac tranny in a swap, and you cant make your car awd sorry man not gonna happen.

burnyd
09-10-2007, 12:12 AM
can you spell alltrac right next time.

extremeskillz
09-10-2007, 12:13 AM
Ricks right. If you had and alltrac making that rwd would be easier.

Murgatroy
09-10-2007, 12:41 AM
It is possible to make your ST185 AWD tranny FWD. Sean uses a modified RC gearbox. it requires extensive modifications, including using MR2 tranny guts. Thus eliminating the rear drive section.

As for making your regular FWD chassis AWD or RWD, it is going to take massive amounts of cash, trial and error and broken parts. But it can be done.

My suggestion would be to find a replacement axle for the transmission you already have. However there are many FWD trannies that can take the abuse of the 3SGTE.

Sean
09-10-2007, 12:47 AM
I broke the half shaft on the first test run.
is there any way to use my alltrack tranny?
is it possible to make it front or rear wheel
only? if not, what do i need to make my 90'
GT an alltrack?

You must of really flogged it on your first test run :hehe:

The GT axles should be okay for the most part, just not launching. You can buy another axle from your auto parts store for probably 60 dollars (the entire axle) with a lifetime warranty.

Making your car RWD is not practical.

Making your car AWD is not practical.

You can use an alltrac transmission, you need to unbolt the transfer case, buy a Mr2 differential with the accompanying Mr2 axles for that differential, a Mr2 Rear Plate cover for where the transfer case used to bolt on to, and alltrac outer axles. On top of that, you will need to completely disassemble your alltrac transmission using special tools such as gear pullers, torx bits, micrometer, lash indicators, et cetera. It's not for the faint of heart. Though perhaps you know someone who doesnt mind getting dirty inside a transmission.

Best bet, is to source a Mr2 gearbox, and go from there.

Cavanagh
09-10-2007, 04:00 AM
A-L-L-T-R-A-C

NO "K"

Thats prolly my biggest pet peeve.

Carolina91GT-S
09-12-2007, 12:10 AM
Sorry for being a Noob and all. I know that everyone says not to use the AllTrac tranny in FWD mode but I can't for the life of me figure out why it wouldn't work. Can someone explain it in detail? Please don't just say it shouldn't be done, i see that all the time but my searches and reading haven't turned up a real answer yet. I always thought that this was the point of these message boards to help each other out and I have the same question as the original poster.

Seems like it all bolts right up just fine, mine even came with the All-Trac axles which seem to fit as well. I just pulled the rear diff off and made a blank off plate. I could either leave it in FWD mode and let the rear gear just drift, or leave it in AWD mode and let the rear gear spin unless the gearbox needs to feel resistance from the absent rear half of the AWD. Either way it isn't connected to anything so it shouldn't be a problem. The AWD tranny came with cooling lines and my replacement radiator came with the cooling loop for them so I have that in place too.

Thanks in advance for any info you guys can provide. And thanks also to the orignal poster for asking the question.

alltracman78
09-12-2007, 12:25 AM
Why don't you try it and see?

It's free [you already have it] and it would be interesting to see what the actual result is.
If you do break it, you will have to source another trans regardless, so you really aren't out anything but $$.

I don't know well the extension housing and related components will fit with your firewall [the Alltrac has a different lower firewall].
I also don't know exactly what you will need to do if you remove part of it, or how the rest will act.

One request if you do.
If it does break, please send me the transfer case [I'll pay shipping].
I want to examine it and see exactly what happened.

Sean
09-12-2007, 12:34 AM
Sorry for being a Noob and all. I know that everyone says not to use the AllTrac tranny in FWD mode but I can't for the life of me figure out why it wouldn't work. Can someone explain it in detail? Please don't just say it shouldn't be done, i see that all the time but my searches and reading haven't turned up a real answer yet. I always thought that this was the point of these message boards to help each other out and I have the same question as the original poster.

Seems like it all bolts right up just fine, mine even came with the All-Trac axles which seem to fit as well. I just pulled the rear diff off and made a blank off plate. I could either leave it in FWD mode and let the rear gear just drift, or leave it in AWD mode and let the rear gear spin unless the gearbox needs to feel resistance from the absent rear half of the AWD. Either way it isn't connected to anything so it shouldn't be a problem. The AWD tranny came with cooling lines and my replacement radiator came with the cooling loop for them so I have that in place too.

Thanks in advance for any info you guys can provide. And thanks also to the orignal poster for asking the question.

http://www.celicatech.com/gallery/files/1/2/MT2.jpg

And here:
http://www.celicatech.com/imagearchive/bgbonline/90alltrac/MT/MT.htm


In the description, it clearly says do not use for daily driving in FF mode. I imagine its half of the engines power is engineered to be transmitted to the rear wheels via the center differential. You would be putting double the stress through the transfer case then its used to seeing. Surely this is not ideal as its not designed for it.

The other big problem, is literally a big problem. The transfer case is heavy, extremely heavy, and you would HAVE to use it to operate the tranny in FWD (unless you opened the transmission, and did some other neat stuff). It would also be smart to seal off the rear prop shaft.... The front shaft that drives the passenger axle cannot be replaced with a normal GTS axle. To not run the transfer case you would have to open the transmission, and install a mr2 differential, and corresponding axles.

alltracman78
09-12-2007, 12:54 AM
I've got to keep this short because I've got 2 papers to work on, but this piqued my curiosity.

I'll start by saying I don't think it will last either.
It's definitely not something I'd do on my car, though in all seriousness if I had a ST184 in addition to my Alltrac it would be interesting to slap one of my spares in it and see how it worked out.

Most importantly IMO, the BGB states it's a bad idea.
Most likely for a reason. I don't see them saying it just so you can't have a FWD turbo...

A couple of things to consider with this debate.

If folks can push 400+ WHP through the trans, I highly doubt 300 crank HP [most folks aren't much beyond that] is going to damamge it from too much power, even if it is only FWD.
However, purely looking at the cautions in the BGB and going by my personal knowledge [good, but by no means all encompassing] it actually sounds like Toyota IS afraid of too much power running through just the front wheels. They specifically limit driving force through the lower torque of 3rd gear and up. High torque 1,2 and R are all excluded from use by them.
If this is the case, it still has to do with the transfer case however, because the MR2T has the same trans minus the Tcase, and it runs just fine on the same [stock] power. Which Toyota obviously knew.
I really need to tear a Tcase apart one of these days and really examine everything with the powerflow chart in my hands.
The problem is time.....

The front diff is open.
So is the center diff [yes it is, read the BGB, it has a viscous coupling that makes it ACT like LSD, but it's not].

The front AND center diff are BOTH housed in the front diff, inside the trans.

Viscous free mode [2nd position on the lever and still 4WD] physically disconnects the viscous coupling from the drivetrain. It gets bypassed.
So the center diff is now by itself and open.

FF mode [front engine/front drive, 3rd and lowest position on the lever, FWD] physically bypasses the center diff. All power now flows from the front diff directly to the 2 front wheels.

Carolina91GT-S
09-12-2007, 01:38 AM
Why don't you try it and see?

I am in the process of attempting this now.


It's free [you already have it] and it would be interesting to see what the actual result is.If you do break it, you will have to source another trans regardless, so you really aren't out anything but $$.

My thoughts exactly


I don't know well the extension housing and related components will fit with your firewall [the Alltrac has a different lower firewall].I also don't know exactly what you will need to do if you remove part of it, or how the rest will act.

I removed the rear transfer housing completely and blanked it off. It looks like it will fit with plenty of room to spare. Once the transfer came out there was no other connection to the transmission. The gear that the transfer meshed with is attached to the shaft inside the transmission via the mode selector and isn't going anywhere. It will staright up spin with the shaft in AWD mode or slip spin in FWD mode.I did take some pictures of this activity with my crappy phone camera but I will try to take better pictures this weekend with a real camera. If someone is in a particular hurry to see these I could upload the phone pics.


One request if you do.
If it does break, please send me the transfer case [I'll pay shipping].
I want to examine it and see exactly what happened.

I'll probably do the same thing...

Murgatroy
09-12-2007, 02:18 AM
I am in the process of attempting this now.

I removed the rear transfer housing completely and blanked it off. It looks like it will fit with plenty of room to spare. Once the transfer came out there was no other connection to the transmission. The gear that the transfer meshed with is attached to the shaft inside the transmission via the mode selector and isn't going anywhere. It will staright up spin with the shaft in AWD mode or slip spin in FWD mode.



I'll probably do the same thing...

I am not certain, never having worked with the transmission, but that would be why others who have done this route used the MR2 differential as well. If a shaft is gone from the transfer case, it could just possibly spin freely.

Carolina91GT-S
09-12-2007, 02:26 AM
In the description, it clearly says do not use for daily driving in FF mode.

I read this too but can't help thinking that this may not be as important with the entire rear portion removed. That would be the drag from the forward rear transfer, rear drive shaft, rear axle transfer, both rear axles, both rear hubs and wheels...all no longer dragging on the transaxle assy.


I imagine its half of the engines power is engineered to be transmitted to the rear wheels via the center differential. You would be putting double the stress through the transfer case then its used to seeing. Surely this is not ideal as its not designed for it.

What about the guys that modify thier All-Tracs, how much power are they putting to the 4 wheels? divide by two. The front wheels portion should be able to handle the 225HP from the JDM 3SGTE shouldn't it? I am hoping, the assy at large is definitely more beefy than the stock tranny on the 5SFE and people use that, at least temporarily. The All-trac front axles came with it and seem to be directly compatible they are much more beefly than the 5S axles as well, again, I'm hoping it works out.


The other big problem, is literally a big problem. The transfer case is heavy, extremely heavy, and you would HAVE to use it to operate the tranny in FWD (unless you opened the transmission, and did some other neat stuff). It would also be smart to seal off the rear prop shaft.... The front shaft that drives the passenger axle cannot be replaced with a normal GTS axle. To not run the transfer case you would have to open the transmission, and install a mr2 differential, and corresponding axles.

I cannot debate the fact that the transmission is a rather large entity. But it will stay in place since it must, I'll deal with the weight, I do not plan to race this car anytime soon. I am using the All-Trac axles and i already blanked off the rear section.


Thanks everyone for your feedback. At this time I still plan to continue since I don't have a definitive reason not to.

Carolina91GT-S
09-12-2007, 02:31 AM
I am not certain, never having worked with the transmission, but that would be why others who have done this route used the MR2 differential as well. If a shaft is gone from the transfer case, it could just possibly spin freely.


There is only one gear that it meshes with, the rear drive gear. I guess to me it seems like that gear with either not spin, so what it isn't driving anything..... or spin so what, it isn't driving anything. I still don't see a down side.

Carolina91GT-S
09-12-2007, 02:48 AM
To the OP...Sorry, I am not trying to hijack your thread

It just might be possible to do what you are thinking about.....

Sean
09-12-2007, 03:17 AM
I read this too but can't help thinking that this may not be as important with the entire rear portion removed. That would be the drag from the forward rear transfer, rear drive shaft, rear axle transfer, both rear axles, both rear hubs and wheels...all no longer dragging on the transaxle assy.



What about the guys that modify thier All-Tracs, how much power are they putting to the 4 wheels? divide by two. The front wheels portion should be able to handle the 225HP from the JDM 3SGTE shouldn't it? I am hoping, the assy at large is definitely more beefy than the stock tranny on the 5SFE and people use that, at least temporarily. The All-trac front axles came with it and seem to be directly compatible they are much more beefly than the 5S axles as well, again, I'm hoping it works out.



I cannot debate the fact that the transmission is a rather large entity. But it will stay in place since it must, I'll deal with the weight, I do not plan to race this car anytime soon. I am using the All-Trac axles and i already blanked off the rear section.


Thanks everyone for your feedback. At this time I still plan to continue since I don't have a definitive reason not to.

We can count the number of seriously modified alltrac's that I know to my knowledge on two hands :) Most of them break fairly quickly as well, so any kind of data is hard to come by.

I'm curious as well! Good luck! Definitely let us know what happens. My argument is, if your going this far to get a great performing car that you've swapped engines, another 80-100lbs up front is not helping the cause at all.

A benefit that I do see from using the transfer case and both complete alltrac axles, is you will have equal length axle, which should help with torque steer.

Carolina91GT-S
09-12-2007, 03:43 AM
I'm curious as well! Good luck! Definitely let us know what happens. My argument is, if your going this far to get a great performing car that you've swapped engines, another 80-100lbs up front is not helping the cause at all.

Actually, after 275k miles the stock transmission lost 5th gear. I told myself that If I ever had to do any real engine or transmission work then I would do a full rebuild. Prior to this I only changed the timing belt and oil pump. Getting rid of the car never entered our minds, we love the 91 GTS. Looking into pricing for kits etc for the engine and a rebuilt tranny, the 3SGTE swap made more sense financially and it came with the tranny etc... It is a side benefit that the 3SGTE happens to be way cool.

I'll let you know how it goes..

P.S. I thought for sure that someone would have done it this way and could provide some feedback considering how many swaps are going on out there.

burnyd
09-12-2007, 03:48 AM
not only that but the small nickle and dime parts are going to kill you on price... your going to need a clutch setup for that car... alltrac/mr2.

Your going to need the trans mounts/rear cross member/axle setup/ carrier bearing bracket.

Just small stuff... that transmission looks complex but good luck if you have the time money and will power. It would just be cheeper and a better move imho to ethier get another celica gt transmission or start out with a solara / mr2 turbo trans.

Sean
09-12-2007, 03:49 AM
Well, I am running a RC edition alltrac transmission. But I installed a Quaife Mr2 LSD to make it work properly minus the transfer case. I have also used two different S-53's, and a mr2 transmission as well on my also 275,000 mile celica :)

Goes to show you how important your data is! Keep us informed.

Sean
09-12-2007, 03:52 AM
Also, to further a point, as you know a transmission is a rather complex system of gears, mesh, and metal. For me it was absolute no man's land until I absolutely had to find a better way of utilizing materials on hand. I think most lack the understanding (including myself) to rationalize what the outcome would be for the setup that your proposing. Thus, it has not happened yet!

Though, from memory I believe a couple people have done this, but ended up reverting to a factory GT transmission.

Carolina91GT-S
09-12-2007, 02:42 PM
not only that but the small nickle and dime parts are going to kill you on price... your going to need a clutch setup for that car... alltrac/mr2.

If I am using the Engine/transmission/clutch combo that was designed for each other and came together, do I still need to change the clutch assy?


Your going to need the trans mounts/rear cross member/axle setup/ carrier bearing bracket.

We can fabricate any mount that I need but the mount came with the clip. I do plan to relocate the lower/rear engine bracket already so I can use my original brace from the 91 GT-S. Is there some reason that I can't use the All-Trac axles? Using the All-trac tranny and All-trac axles will eliminate the need for the carrier bearing backet(if it is what I think it is)


Just small stuff... that transmission looks complex but good luck if you have the time money and will power. It would just be cheeper and a better move imho to ethier get another celica gt transmission or start out with a solara / mr2 turbo trans.

I got the whole engine clip including tranny, axles, ecu, all sensors, wiring, etc...

If this works it will be far cheaper and easier than any other course of action.

If Burn is directing his post at the OP then I will again apologize to the OP for hijacking. I just think this is a good topic. And the OP is already in a slightly different set of circumstances so the discussion isn't quite paralell

burnyd
09-12-2007, 02:56 PM
If I am using the Engine/transmission/clutch combo that was designed for each other and came together, do I still need to change the clutch assy?

I didnt realize you were a different person than the thread starter.... He was still on a stock gt transmission... if you are running that transmission in the car you will need the clutch assy for a mr2/alltrac.....




We can fabricate any mount that I need but the mount came with the clip. I do plan to relocate the lower/rear engine bracket already so I can use my original brace from the 91 GT-S. Is there some reason that I can't use the All-Trac axles? Using the All-trac tranny and All-trac axles will eliminate the need for the carrier bearing backet(if it is what I think it is)

Assumign you have a clip you will not need to fabricate. Unfortunately I could not find a cross membe that I needed for my 6th gen celica and I had to make a mount every month when it came to my car... it wouldnt of broken all the time on my swapped car grant it I had the right cross member/rear transmission mount.




I got the whole engine clip including tranny, axles, ecu, all sensors, wiring, etc...

If this works it will be far cheaper and easier than any other course of action.

If Burn is directing his post at the OP then I will again apologize to the OP for hijacking. I just think this is a good topic. And the OP is already in a slightly different set of circumstances so the discussion isn't quite paralell

If you have the entire thing then just go ahead and try to swap the entire drivetrain in your fwd car and let us know what happens. But if you have the entire clip you will have all the converstion parts antway...... even if for some reason it does not work you will have all the converstion parts to make a mr2 transmission work/solara transmission work.

Carolina91GT-S
09-17-2007, 03:07 AM
I did work on the car this weekend but haven't gotten it into driving condition yet. This weekend was brake caliper painting and rebuild, wheel bearing overhaul, steering rack boot replacement, installing new tie rod ends & lower ball joints, cleaning the engine compartment, blah blah blah, right now the 3SGTE( with AllTrac tranny) is still sitting on the stand wondering when it gets to meet the GT-S. Anyway...I will update this thread with progress regarding the whole AllTrac tranny thing and if it works or doesn't.

Mr Celica
09-17-2007, 04:05 AM
can you use the s52 transmission (out of 88-91 V6 camry)? does that bolt up to the 5sfe/3sgte?

what are the differences between the 5sfe tranny (e53 i think?) and the s52?

Sean
09-17-2007, 07:27 AM
Pics would be great as well :) We like pics!

Carolina91GT-S
09-24-2007, 11:39 PM
No update after this weekend. I didn't work on it at all. I spent the weekend on the class V+ white water rapids of the mighty Gauley river in WV.

Carolina91GT-S
10-29-2007, 06:38 PM
I am almost finished with the wiring harness extensions etc, the engine/XMSN will be going into the car soon. I haven't forgotten to update this, it's just the work I have been doing to the car isn't relevant to this discussion specifically. The engine swap is a fair amount of work by itself without concerning the XMSN stuff. I have been taking pictures but I cannot find the cable to download from the camera. I am planning to put together a detailed explanation of this afterward...if it works. I'll update this thread with the result but will start a new thread with the explanation.

Is it better to generate a web page to detail it? or to do it in a thread? if I did it in web page format could it posted on the Celicatech server if it was of decent quality?

Sean
10-29-2007, 10:51 PM
Do it in word, then paste it over in a thread. I will make it a sticky if its good :)

alltracman78
11-01-2007, 10:28 PM
Well, I have an update anyways.

I had to tear apart and sort out a bunch of trans stuff, so I tore down one of my T cases all the way.

As far as I can tell it does come down to strength. In the viscous free mode only part of the splined shaft is used [roughly 1/2"].
In FF [Front engine/Front drive] mode, there are notches in the sleeve that connect the center diff directly to the front diff and bypass the propellor shaft. I don't know how much power they can handle.

I don't have pictures at the moment, if I get a chance I will but it's going to take a shitload to show everyone so they understand.....

Carolina91GT-S
11-02-2007, 01:47 PM
I see what you are getting at with your description.

In AWD drive mode though the whole connection is strong? meaning that the transfer or force happens along a mechanical path that easily has the strength to support that force?

Hopefully you would be willing to answer this since you are the only person that I know of right now that has a ALL trac XMSN opened up... If the XMSN was in AWD drive mode and the rear portion felt no resistance...for example, the rear drive shaft broke on both ends and fell off, would the two front wheels still drive correctly?

I am thinking that maybe I can leave it in AWD mode and run it in a FWD application. This would allow the gear that is connected to the front wheels to operate normally under full strength connection and the rear transfer would operate normally, spinning, but driving nothing. I have removed the prop shaft so the gear will spin inside the transfer housing. It will have no rear load on it but it will feel the front wheel load since it is in AWD mode. Would the transfer slip in this configuration?

Am I making sense?