The Subaru SVX World Network   SVX Network Forums
Live Chat!
SVX or Subaru Links
Old Lockers
Photo Post
How-To Documents
Message Archive
SVX Shop Search
IRC users:

Go Back   The Subaru SVX World Network > SVX Main Forums > Technical Q & A

Reply
 
Thread Tools Display Modes
  #1  
Old 02-03-2014, 12:58 PM
NiftySVX NiftySVX is offline
Registered User
 
Join Date: Sep 2002
Location: Oklahoma City, Oklahoma
Posts: 836
Send a message via AIM to NiftySVX
Donor rear diffs

Hello all, It looks like I am going to be replacing my level ten paperweight with a 3.70 ratio trans.

WHO KNOWS the specifics of the diff compatibility? If it has 5 bolts for the side plates will it work? I am having some trouble locating a 3.70 rear diff.

SVXfiles? Anyone?
__________________
2007 GS 450h-Active Stabilizer/Radar cruise
1994 L Blue 3.70 VTD



ASE Master Automobile
ASE Advanced Level Specialist
Toyota Master Diagnostic Technician (former life)
Reply With Quote
  #2  
Old 02-03-2014, 02:04 PM
92 SVX 92 SVX is offline
Registered User
 
Join Date: Feb 2010
Location: Jax Florida
Posts: 1,469
Registered SVX
Re: Donor rear diffs

I can understand wanting to stay auto but why not go 4.44 gears?
Reply With Quote
  #3  
Old 02-03-2014, 02:18 PM
Tireiron Tireiron is offline
Registered User
 
Join Date: Apr 2012
Location: Methuen, MA
Posts: 266
Re: Donor rear diffs

Where are you coming across a 3.70 in the US? There were almost no Subaru's built with 3.70 in this country. Almost exclusively limited to the 06/07 WRX manual.

Your best option aside from getting an overseas SVX 3.70 rear diff is to swap the r160 3.70 ring and pinion gear into your SVX r160. You cannot swap the WRX r160 in because the SVX axle shafts will not fit the WRX diff, and the WRX axle shafts will not fit the SVX rear knuckles. You maybe able to find a used diff to get the gears from, but if not you can still get them new from Subaru and I think ralli spec.
Reply With Quote
  #4  
Old 02-03-2014, 02:22 PM
92 SVX 92 SVX is offline
Registered User
 
Join Date: Feb 2010
Location: Jax Florida
Posts: 1,469
Registered SVX
Re: Donor rear diffs

Quote:
Originally Posted by Tireiron View Post
Where are you coming across a 3.70 in the US? There were almost no Subaru's built with 3.70 in this country. Almost exclusively limited to the 06/07 WRX manual.

Your best option aside from getting an overseas SVX 3.70 rear diff is to swap the r160 3.70 ring and pinion gear into your SVX r160. You cannot swap the WRX r160 in because the SVX axle shafts will not fit the WRX diff, and the WRX axle shafts will not fit the SVX rear knuckles. You maybe able to find a used diff to get the gears from, but if not you can still get them new from Subaru and I think ralli spec.
Actually thats not a bad idea, get the euro/jdm vtd trans and tcu and worse case get wrx 3.7 gears and swap into svx diff.

If I was thinking about staying auto that may be my plan.
Reply With Quote
  #5  
Old 02-03-2014, 02:40 PM
NiftySVX NiftySVX is offline
Registered User
 
Join Date: Sep 2002
Location: Oklahoma City, Oklahoma
Posts: 836
Send a message via AIM to NiftySVX
Re: Donor rear diffs

There were a ton of subarus made in the 80s with 3.70. I know I will have to swap the gears in. That's what I want to know.

I don't want to go to 4.44 because that is too tall of a gear for this car. I was considering 4.11 but 3.70 is easier because I can build a trans based on a FWD svx unit. I have three of them. Plus if I can get a VTD trans I can bolt it in.
__________________
2007 GS 450h-Active Stabilizer/Radar cruise
1994 L Blue 3.70 VTD



ASE Master Automobile
ASE Advanced Level Specialist
Toyota Master Diagnostic Technician (former life)

Last edited by NiftySVX; 02-03-2014 at 02:44 PM.
Reply With Quote
  #6  
Old 02-03-2014, 04:44 PM
Blacky Blacky is online now
51 Club
 
Join Date: Aug 2008
Location: LSM, Quebec
Posts: 2,534
Registered SVX
Re: Donor rear diffs

A 1980's tranny will not bolt up to an EG33 engine. 4.44 is a lower ratio than the stock diff. and is very well suited to the SVX engine. The 4.44 is also known to be much more durable than stock. 4.11 trannys are weak and fail often on an SVX.
Reply With Quote
  #7  
Old 02-03-2014, 04:54 PM
NiftySVX NiftySVX is offline
Registered User
 
Join Date: Sep 2002
Location: Oklahoma City, Oklahoma
Posts: 836
Send a message via AIM to NiftySVX
Re: Donor rear diffs

I am not talking about the transmissions. I am going to build the transmission. Trust me I'm an expert on the 4EAT. No matter what ratio I go with it will be the big daddy 4eat with 5 clutch plates.

I have a stack of these transmissions. I can put any gear I want in the transaxle. That isn't what I am talking about.

I do not want a 4.44 ratio. I don't want a gear that tall. I'm not interested in an SVX that is geared that tall.

What I need to know is if I can combine the 80s 3.70 R160 and the SVX 3.545 VLSD
__________________
2007 GS 450h-Active Stabilizer/Radar cruise
1994 L Blue 3.70 VTD



ASE Master Automobile
ASE Advanced Level Specialist
Toyota Master Diagnostic Technician (former life)

Last edited by NiftySVX; 02-03-2014 at 04:59 PM.
Reply With Quote
  #8  
Old 02-03-2014, 07:36 PM
92 SVX 92 SVX is offline
Registered User
 
Join Date: Feb 2010
Location: Jax Florida
Posts: 1,469
Registered SVX
Re: Donor rear diffs

if you want 3.7 gears why not just grab a wrx the years listed, then transfer just the gears into the svx diff. keeping the svx's vlsd and axles?
Reply With Quote
  #9  
Old 02-03-2014, 07:41 PM
Tapani Tapani is offline
Registered User
 
Join Date: Feb 2010
Location: Finland
Posts: 815
Registered SVX
Re: Donor rear diffs

Quote:
Originally Posted by NiftySVX View Post
I do not want a 4.44 ratio. I don't want a gear that tall. I'm not interested in an SVX that is geared that tall.

What I need to know is if I can combine the 80s 3.70 R160 and the SVX 3.545 VLSD
Yes you can. I have done two. You may need to grind the casting a bit for the LSD to clear (assembly only). While your at it, why not throw in a Quaife Torsen in the rear and a Modena TBD in the front ;-)?

Tapani
Attached Images
File Type: jpg diffs.jpg (164.9 KB, 111 views)
Reply With Quote
  #10  
Old 02-03-2014, 07:57 PM
NiftySVX NiftySVX is offline
Registered User
 
Join Date: Sep 2002
Location: Oklahoma City, Oklahoma
Posts: 836
Send a message via AIM to NiftySVX
Re: Donor rear diffs

Because a WRX diff is going to cost me a lot more. I know I need to use the SVX axles. I will have to call my source and make sure it is a 5 bolt diff before I buy.
__________________
2007 GS 450h-Active Stabilizer/Radar cruise
1994 L Blue 3.70 VTD



ASE Master Automobile
ASE Advanced Level Specialist
Toyota Master Diagnostic Technician (former life)
Reply With Quote
  #11  
Old 02-03-2014, 09:20 PM
Tireiron Tireiron is offline
Registered User
 
Join Date: Apr 2012
Location: Methuen, MA
Posts: 266
Re: Donor rear diffs

All r160 diffs use the same size gear sets, so just put the 3.70 gears into the SVX housing with the SVX carrier and LSD.
Reply With Quote
  #12  
Old 02-03-2014, 09:36 PM
NiftySVX NiftySVX is offline
Registered User
 
Join Date: Sep 2002
Location: Oklahoma City, Oklahoma
Posts: 836
Send a message via AIM to NiftySVX
Re: Donor rear diffs

Some aren't compatible. I Will just buy this unit and hope I can swap it and don't have to remove the pinion from the case since no one knows anymore…..
__________________
2007 GS 450h-Active Stabilizer/Radar cruise
1994 L Blue 3.70 VTD



ASE Master Automobile
ASE Advanced Level Specialist
Toyota Master Diagnostic Technician (former life)
Reply With Quote
  #13  
Old 02-03-2014, 10:23 PM
Tapani Tapani is offline
Registered User
 
Join Date: Feb 2010
Location: Finland
Posts: 815
Registered SVX
Re: Donor rear diffs

Quote:
Originally Posted by NiftySVX View Post
hope I can swap it and don't have to remove the pinion from the case since no one knows anymore…..
Just protect the pinion bearings with a rag when you grind the housing to clear the LSD. I tried to find a photo of the exact spot - no luck.

/T
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 06:37 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
© 2001-2015 SVX World Network
(208)-906-1122