5EAT Ask your Questions!?!

I'm building an 818 and am thinking of using a 3.6 with auto. This will require shortening the tranny and converting to FWD, (which in an 818 would be RWD).

 

Can the 5EAT be converted to FWD? Can the the AWD clutch pack be removed, the tail section removed? The goal would be to make it as short and light as possible.

 

Thanks.

Why not use a 4eat?

Why not use a 4eat?

I was under the impression the 4EAT was not as strong as the 5EAT, is that incorrect?

 

The 818 will be a race car, the 818R version. It will be under a lot of stress, potentially for many hours in an endurance race. It needs to shift hard and fast, up and down, under manual control with paddle shifters. Comfort of the shift is not a factor.

 

And the gearing has to work for a 165 mph top speed at 6400 rpm.

 

The same questions apply to the 4EAT. Although I know the fuse trick to make it FWD. We have one other builder who has cut the tail off a 4EAT but I don't think he took out any internals. He just cut the tail off and fabricated a plate to cover the hole. His car is not an R version though, he's building a standard weekend driver, the 818S.

 

Thanks for your reply.

Gator

Edited November 26, 2015 by Sgt.Gator

I believe you will have to bind or well up the CD, since with the open diff, the 5EAT is semi rear bias. I will see if I can get that from the manual.

the 4 eat appears to be stronger because it doesnt have a center diff ( except the vdc models)

 

if you want to use a 5 eat and use only the front differential your going to have to weld something up. it may or may not be reliable as the gear set isn't meant for all the power on one differential. i have removed my center diff and made it selective rwd or 4wd. but then i broke the rear diff shortly after.

Thanks for your replies.

Will the 4EAT work with a 3.6 and ECU that originally had a 5EAT tranny?

 

Most builders are looking at a 3.0 or 3.6 mated to a 5 or 6 speed manual tranny. But that then requires dumping the Subaru ECU and using an aftermarket ECU. If I can pull a 3.6 out of a Tribeca or Legacy with it's tranny and ecu that simplifies things considerably.

 

There are other issues with the Legacy 5th gen motor mounts we are trying to resolve, so the Tribeca is the easiest route. 3.6 Legacys use a front mount, Tribecas all use the side mounts like a 4th gen Legacy/WRX/STI 2.5, which the 818 frame was designed for.

 

Happy Thanksgiving everyone!

I doubt the stock ecu will work with the 4 eat.

 

You could make the ecu think its manual and then use stand alone trans control unit like megashift from megasquirt.

 

Or do even more basic with 2-3 micro switches and a ratchit shifter and you will have full manual controle auto as i have done in the past.

Full manual control would be fine. Is there a thread on doing that?

I did one on v6z24.com

I recently replaced my 200k miles oem driveshaft with a dorman unit, (that fits but the ears of the middle universal hit the tunnel under load). I'll be sending it back obviously, but I seem to recall hearing that the 5eat driveshaft was the same length and config as the 2004 ish STI? I'd like to go with a one piece aluminum shaft with serviceable bits. Will the shaft at the link below fit or do i just need to have one custom made?

 

http://www.driveshaftshop.com/import-driveshafts/subaru/sti-2004-2007/subaru-1-piece-aluminum-driveshafts-for-wrx-and-sti-04-07-sti-r180-rear

 

Below are some pics of the Dorman shaft and where it is hitting.

http://images.tapatalk-cdn.com/15/12/07/64274f3e05282e447a2522089905cab5.jpg

http://images.tapatalk-cdn.com/15/12/07/5cb1e5f8c6b1504d27110e8310f0d1d9.jpg

That'd be some very useful info to have. Hope it pans out...I could use a new 1-piece driveshaft.

Well it seems as though the 4eat auto shaft will work when doing a 5MT to 6MT swap. Not the 5EAT i was thinking of.

Yes it always seems so.

I've been wondering about two things. 1.) I've noticed a few members use aftermarket transmission coolers. Are these just something you'd use if you track your car? 2.) not really a 5EAT question but my car has a noticeable thunk when you hit the gas quick, guessing it's the differential bushings? I've seen the white line kit and wanted an opinion on it. It seems like a good idea to stiffen it up. The WRX diff moves quite a bit. Wasn't sure if the Leggy was the same way, just how it works stock.

I've been wondering about two things. 1.) I've noticed a few members use aftermarket transmission coolers. Are these just something you'd use if you track your car? 2.) not really a 5EAT question but my car has a noticeable thunk when you hit the gas quick, guessing it's the differential bushings? I've seen the white line kit and wanted an opinion on it. It seems like a good idea to stiffen it up. The WRX diff moves quite a bit. Wasn't sure if the Leggy was the same way, just how it works stock.

 

Heat is a transmissions enemy so the cooler is a good way to prolong the life of it. plus allows you to handle a bit more power.

For those who have had rear diff failures, what symptoms were you having?

 

My car started making a grinding/popping noise coming from the back tonight.

 

 

It was one of those "hey watch this" moments

For those who have had rear diff failures, what symptoms were you having?

 

My car started making a grinding/popping noise coming from the back tonight.

 

 

It was one of those "hey watch this" moments

 

Smh, did you try to brake boost?

Could be one of the inside ends of an axle has started to come out. Pop it back in and the sounds should go away.

 

I've had two failures. First was the pinion bearings. Makes a whining noise.

Second was a siezure of the driver's side axle bearing. That will show up as trans slipping and smoke the clutch disks in your trans pretty quick.

I'll check the axles tonight. Someone I know had a similar issue with an OBXT.

 

It's a stg3 car with a 20g. Brake boosted to ~10psi@3k and launched.

Dont mistake me asking for me being surprised.

 

I have an extra trans+rear diff at a friends house.

Hi looking for any recommendations for Transmission builders for the 5EAT. Running fairly high horsepower 400WHP and am looking for improved performance and longevity. Anyone out there besides IPT?

 

THANKS

HORTONHEAT

You want hexmods(climberD) VB and diff bushings.

 

If you truly are pushing 400whp+(larger than a 20g) you may want to look into some of the services IPT offers.

I already have the Hexapods Valve Body and the CD bearing upgrades. But I have 170K on the trans and would like more grip on the low end since autocross will be my primary focus. Clutch packs and different torque converter maybe the answer. That maybe IPT but am looking for options on builders since I live in Indianapolis.

Our 5EATS are fast, but not around a track/autocross course. If AutoX is your focus, get a 5MT/6MT Legacy, or a Miata. You will always fall just a little short without a stickshift. As for 5EAT racing, If built correctly and you have deep pockets, its got great potential to be a decent 1/4 mile car...you already have the bushings so that's a start. I'm jealouse of that BTW. Other than that, they are phenomenal DD's for city driving.

I dissagree about the autox... I have a miata and lgt.

I already have the Hexapods Valve Body and the CD bearing upgrades. But I have 170K on the trans and would like more grip on the low end since autocross will be my primary focus. Clutch packs and different torque converter maybe the answer. That maybe IPT but am looking for options on builders since I live in Indianapolis.

 

Honestly the best way would be the Hexmod VB and the IPT rebuild. Theres not many who rebuild. You can always order the stuff from them and have someone else build it.