Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Transmission (AT/MT) & Driveline

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 11-03-2020, 04:44 PM   #1
EastPhilly
Scooby Newbie
 
Member#: 491030
Join Date: Sep 2018
Default Was told my center diff snap ring broke from overheating.

My trans was being weird and clunky, with a lot of shavings in the fluid. I took my car to RalliSpec for a refresh and they told me the center diff must have overheated and the snap ring broke. I'm guessing that is caused by uneven wear off the tires? I only had one time a tire for messed up very soon after buying a set, and I drove maybe .5 miles with the spare. I was worried about messing it up, so I stopped every couple blocks for a few minutes. But that was maybe 12/18 right after I bought the car.

I'm working on lifting the car a bit, so I bought taller tires on smaller wheels. About 6 months later is when the weirdness started. Those wheels/tires are actually lighter than my stock setup, so I don't think it's those though.

In early 2019 I had an axle snap and drove on it for a day since my mechanic though it may have been a synchro being broken with the way I described it over the phone. I had to drive about 50 miles home and was another ~30 the next day until I could get it to him. It would catch and work fine once I got rolling, but was skipping a bit on starts.

What usually causes a diff to overheat? How can I avoid it in the future?
Any other ideas? Just general wear after 126k miles? Fluid got too low?
* Registered users of the site do not see these ads.
EastPhilly is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 11-04-2020, 08:48 AM   #2
Unabomber
Big Ron
Super Moderator
 
Member#: 18062
Join Date: Apr 2002
Chapter/Region: MAIC
Location: I can save you a ton of cash
Vehicle:
on car parts so PM
me b4 j00 buy

Default

Your center diff explodes due to age, bad luck or running uneven tire diameters. Spin the wheel and take your pick. There is no fluid too low as that unit is sealed.
Unabomber is offline   Reply With Quote
Old 11-05-2020, 11:39 AM   #3
cboggess
Scooby Specialist
 
Member#: 30804
Join Date: Dec 2002
Chapter/Region: SWIC
Vehicle:
87 Yugo
Red

Default

I have seen this happen a few times now. in summary it sucks. I know that's not really helpful, but I understand your pain.
cboggess is offline   Reply With Quote
Old 11-05-2020, 01:03 PM   #4
JarHarms
Scooby Specialist
 
Member#: 138994
Join Date: Jan 2007
Location: apparently I "spread the hate"
Vehicle:
2006 WRX, 6MT, 5x114

Default

If the snapped axle you drove on was a rear axle; I would expect that is the majority of your root cause. That slipping clutch feel until it starts rolling as you described. This places a lot of strain (overheat) on the center viscous coupling. Followed up with age, use, and it likely being the older cir-clip Cdiff. Likely not low gear oil level since the Cdiff is a sealed unit filled with it's own viscous fluid.
You are going to need a new Cdiff of course. Likely the Cdiff cir-clip was ingested by the transfer gears so you may need a new transfer gear set, bearings, etc.


Quote:
Originally Posted by EastPhilly View Post
Hey all, this will be about my 2007 WRX Wagon w/ 126k miles...?
You should put this in your profile or at least include in your OP so we know what vintage car/parts you are dealing with.
JarHarms is offline   Reply With Quote
Old 11-05-2020, 01:45 PM   #5
T-37
Scooby Specialist
 
Member#: 175624
Join Date: Mar 2008
Chapter/Region: MWSOC
Location: Wichita, KS
Vehicle:
0304 WRX WRX
SY WRB

Default

Quote:
Originally Posted by Unabomber View Post
Your center diff explodes due to age, bad luck or running uneven tire diameters. Spin the wheel and take your pick. There is no fluid too low as that unit is sealed.
Don't forget the ol' handbrake of doom.
T-37 is offline   Reply With Quote
Old 11-05-2020, 08:04 PM   #6
EastPhilly
Scooby Newbie
 
Member#: 491030
Join Date: Sep 2018
Default

Quote:
Originally Posted by JarHarms View Post
You should put this in your profile or at least include in your OP so we know what vintage car/parts you are dealing with.
Didn't realize I didn't do that. Yea. I figured it was a culmination of this being my first stick car (I drive motorcycles a lot, so the learning curve wasn't terrible), that axle breaking, and maybe a clutch that's a little too heavy. RalliSpec didn't have a new one, so he threw a good used one in.
EastPhilly is offline   Reply With Quote
Old 11-05-2020, 08:29 PM   #7
JarHarms
Scooby Specialist
 
Member#: 138994
Join Date: Jan 2007
Location: apparently I "spread the hate"
Vehicle:
2006 WRX, 6MT, 5x114

Default

FYI the newest Subaru part number Cdiff has a c-clip instead of the older cir-clip. The c-clip is more robust and it would be attached to a new Cdiff.
JarHarms is offline   Reply With Quote
Old 11-05-2020, 09:37 PM   #8
EastPhilly
Scooby Newbie
 
Member#: 491030
Join Date: Sep 2018
Default

Quote:
Originally Posted by JarHarms View Post
FYI the newest Subaru part number Cdiff has a c-clip instead of the older cir-clip. The c-clip is more robust and it would be attached to a new Cdiff.
This was all put together a couple days ago by RalliSpec. I got it back and already having a few problems. Only one I think is related to their job though. I've only driven the car on 4 trips since getting it back. Each trip, about 5 minutes into the drive, I will start in 1st gear from a stop and it will pop out of 1st gear into neutral. The first one I barely noticed and thought I just forgot to put it in gear. Second time I heard a bump and it did it. This morning sounded more like a pop. And an hour ago it was super loud when I tried to accelerate and it came out of gear. Three of the four times it happened the CEL came on with a neutral switch high circuit voltage. I got the trans refreshed (new bearings, synchros, bushigs, etc...). While it was there I got the PDM snout kit installed as well. Could either of these be a part of the problem?I definitely feel the car a good bit more since I'm guessing they arent broken in yet.

Second problem is a weird idle. IT sits at regular idle, then goes up a couple hundred rpm and goes lower than normal, then back to normal. It'll do it a couple times at each red light. Then tonight I was reversing out of a parking spot. I went from reverse to 1st and realize the car had stalled out (I had neutral in so there was no jump). I'm guessing maybe I developed a vacuum leak somewhere?

Third is my P/S axle. He mentioned something about it clicking, and I thought he meant the light whine/tick it made on super tight turns. But I ent to park later that night and it's extremely jumpy at tight turns. Definitely not how it was before I dropped it off.
EastPhilly is offline   Reply With Quote
Old 11-06-2020, 12:11 PM   #9
JarHarms
Scooby Specialist
 
Member#: 138994
Join Date: Jan 2007
Location: apparently I "spread the hate"
Vehicle:
2006 WRX, 6MT, 5x114

Default

The popping out of gear into N is likely a gear stack assembly issue. I WOULD NOT DRIVE THIS ANYMORE UNTIL you let Rallispec know about this. I am sure they will take care of that.
The Neutral Position Switch (NPS) harness plug might not be connected well or possibly it has an electrical issue. [or if there was ALOT of gear stck slop...maybe but unlikely..just thinking] This could also be a potential cause of your idle issue. I would not expect a strait trans R&R to affect vacuum lines but still worth checking out. I doubt the PDM Snout Kit has anything to do with this issue.
Axle shaft P/S passenger side front or rear? I am guessing front since rears would not have been touched during a trans R&R. Make sure both ends are seated into place correctly, looks for leaking/torn boots, etc. If Rallispec re-works the trans have them look at the axle CV joints during that job.
Good luck
JarHarms is offline   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 -4. The time now is 05:25 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.