1m diff problem

ahtim · 10-01-2021, 08:45 PM

Hi, how can you tell of your diff is going to worn out or not?
My car had 51k km on the clock, had the car since new and mostly on highway driving slowly. A week ago I changed my subframe and diff bushings and they realize that the right side seal is a bit wet( moist) not dropping at all, so they ordered a new seal(only one in stock) and replaced the right side and changed fluid, then I drove the car to do alignment which is around 35km distance and realize the left side is leaking badly onto the exhaust.
Does anyone know what is happening? The left side was perfectly dry, and after changing the right side, the left Is leaking badly

Thanks in advance

nachob · 10-01-2021, 09:31 PM

Quote:

Originally Posted by ahtim

Hi, how can you tell of your diff is going to worn out or not?
My car had 51k km on the clock, had the car since new and mostly on highway driving slowly. A week ago I changed my subframe and diff bushings and they realize that the right side seal is a bit wet( moist) not dropping at all, so they ordered a new seal(only one in stock) and replaced the right side and changed fluid, then I drove the car to do alignment which is around 35km distance and realize the left side is leaking badly onto the exhaust.
Does anyone know what is happening? The left side was perfectly dry, and after changing the right side, the left Is leaking badly

Thanks in advance

Not sure if you jostled something when changing bushings but those deals are 10 years old and they start to leak. I had mine replaced a year ago. Also only did the right side but possible left side could go too. I didn't know if maybe I just got a bad right side seal and it was a bit expensive so that's why I did just one side. If I would've read this today and it seems more likely both could go at the same time I might have preemptively changed both.

As to why all of sudden the left let go. It could just be coincidence or maybe whale changing bushings so new load could've been put in the halfshafts that made the 10 year old seal give out. This is a tough one. Sorry it happened. Luckily you caught before diff runs dry.

ahtim · 10-01-2021, 10:39 PM

How can you check or tell if the diff is done or not? Shall I replaced the left seal and see how it goes? Or is my diff worn out and require a rebuild ?

671rover · 10-02-2021, 05:39 AM

Is there a breather for the diff? Perhaps the breather is blocked? Diff fluid heats up when driving and creates pressure in diff and since you changed your right seal the left becomes the weak point. Happens with my defenders when axle breathers are blocked. Let us know.

ahtim · 10-02-2021, 07:15 PM

Quote:

Originally Posted by 671rover

Is there a breather for the diff? Perhaps the breather is blocked? Diff fluid heats up when driving and creates pressure in diff and since you changed your right seal the left becomes the weak point. Happens with my defenders when axle breathers are blocked. Let us know.

I asked the garage who changed my right side seals, and they said they didn't do a mark on the position when they remove the seals, I wonder if that could cause the problem?

671rover · 10-03-2021, 02:01 AM

Marking the position of the seal wouldn't make any difference unless the seal has some sort of position it needs to go in. The breather I'm referring to is a vent for the differential. If the vent is blocked or obstructed then once the pressure builds up in you diff from heat, fluid will leak from the seals that are weak/old. You said you changed your right side seal, now that seal is nice and tight and if the breather/vent is blocked then it'll cause the fluid leak from other seals. And if you change your left seal and the breather/vent is still blocked then the pinion seal will probably leak.

PRTSB1M · 10-04-2021, 08:04 AM

Quote:

Originally Posted by ahtim

How can you check or tell if the diff is done or not? Shall I replaced the left seal and see how it goes? Or is my diff worn out and require a rebuild ?

It should be very obvious when the diff is bad.

ahtim · 10-06-2021, 12:52 PM

Quote:

Originally Posted by PRTSB1M

Quote:

Originally Posted by ahtim

How can you check or tell if the diff is done or not? Shall I replaced the left seal and see how it goes? Or is my diff worn out and require a rebuild ?

It should be very obvious when the diff is bad.

Changed the seals and drove 30km with it, very dry, problem fixed, the old seal is very hard and worn out

PRTSB1M · 10-06-2021, 05:53 PM

Quote:

Originally Posted by ahtim

Changed the seals and drove 30km with it, very dry, problem fixed, the old seal is very hard and worn out

Glad you got it figured out

I've read that the diff should be good mechanically until at least 70-80k miles, where some have reported (bearing?) failures in the shorter shaft/pump side of the factory GKN unit.

10-01-2021, 08:45 PM	#1
ahtim Akrapovic HK 68 Rep 265 Posts Drives: mostly NA, sometimes turbo Join Date: Oct 2008 Location: Hk/ China / UK iTrader: (0)	1m diff problem Hi, how can you tell of your diff is going to worn out or not? My car had 51k km on the clock, had the car since new and mostly on highway driving slowly. A week ago I changed my subframe and diff bushings and they realize that the right side seal is a bit wet( moist) not dropping at all, so they ordered a new seal(only one in stock) and replaced the right side and changed fluid, then I drove the car to do alignment which is around 35km distance and realize the left side is leaking badly onto the exhaust. Does anyone know what is happening? The left side was perfectly dry, and after changing the right side, the left Is leaking badly Thanks in advance
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10-01-2021, 10:39 PM	#3
ahtim Akrapovic HK 68 Rep 265 Posts Drives: mostly NA, sometimes turbo Join Date: Oct 2008 Location: Hk/ China / UK iTrader: (0)	How can you check or tell if the diff is done or not? Shall I replaced the left seal and see how it goes? Or is my diff worn out and require a rebuild ?
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10-02-2021, 05:39 AM	#4
671rover Private First Class 18 Rep 173 Posts Drives: '94 D90, '95 D90 SW, '11 VO 1M Join Date: Sep 2009 Location: (671) iTrader: (0)	Is there a breather for the diff? Perhaps the breather is blocked? Diff fluid heats up when driving and creates pressure in diff and since you changed your right seal the left becomes the weak point. Happens with my defenders when axle breathers are blocked. Let us know.
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10-03-2021, 02:01 AM	#6
671rover Private First Class 18 Rep 173 Posts Drives: '94 D90, '95 D90 SW, '11 VO 1M Join Date: Sep 2009 Location: (671) iTrader: (0)	Marking the position of the seal wouldn't make any difference unless the seal has some sort of position it needs to go in. The breather I'm referring to is a vent for the differential. If the vent is blocked or obstructed then once the pressure builds up in you diff from heat, fluid will leak from the seals that are weak/old. You said you changed your right side seal, now that seal is nice and tight and if the breather/vent is blocked then it'll cause the fluid leak from other seals. And if you change your left seal and the breather/vent is still blocked then the pinion seal will probably leak.
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