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limepanda

Mixing Diff Fluid Brands?

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So I'm all prepped to do a fluid change on my E90 335i's rear diff, unfortunately I've only got 950mls of AMSOIL Severe Gear 75w90 and the diff holds about 1.2 litres.

Is it ok to drain the old stuff out, add all the new fluid and then fill the last 250mls with the old fluid? (Which I assume is Castrol Syntrax Long Life 75w90).

Or would it be better to just wait until I can get my hands on another litre of AMSOIL?

They're both rated API GL-5 for what it's worth.

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Whats the point of doing a fluid change if you are reusing some of the oil.

 

You wouldnt do it to your engine so dont do it to your diff.

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Half the reason we do oil changes is to remove the contaminants so not smart to put them back into fresh oil

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Penrite progear 75w90 from supercheap. Its cheap. and pretty super. 

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4 hours ago, zero said:

Whats the point of doing a fluid change if you are reusing some of the oil.

 

You wouldnt do it to your engine so dont do it to your diff.

 

3 hours ago, 3pedals said:

Half the reason we do oil changes is to remove the contaminants so not smart to put them back into fresh oil

Yeah pretty much what I was thinking, was tossing up doing it as more a flush and do it again sometime in the next few weeks as there's no drain plug so there's no way I'll be getting all of it out anyway.

 

41 minutes ago, Jacko said:

Penrite progear 75w90 from supercheap. Its cheap. and pretty super. 

I thought about it but I know the AMSOIL works great for it and is rated extremely well which I think is even more important given this diff is somewhat under-engineered.

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"lifetime" transmission fills to "lifetime diff fills. Who would of thought.

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I promise I am not a FCP shill. I recently thought about doing a diff fluid flush and as it turns out you can buy fluid and drain/fill plugs from FCP, ship them here and pay gst for less than the cost of buying two liters of fluid from SCA. 

  • Haha 1

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42 minutes ago, Gabe79 said:

I promise I am not a FCP shill. I recently thought about doing a diff fluid flush and as it turns out you can buy fluid and drain/fill plugs from FCP, ship them here and pay gst for less than the cost of buying two liters of fluid from SCA. 

What are the rules around shipping fluids? I just checked FCP (I love them by the way), and for my car it would cost about $150, much more than buying the fluid here.

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7 hours ago, limepanda said:

What are the rules around shipping fluids? I just checked FCP (I love them by the way), and for my car it would cost about $150, much more than buying the fluid here.

Alright, I have to correct myself a bit. I haven't priced the diff drain/ill plugs locally, so this is an apple to oranges comparison of Penrite diff fluid at SCA versus E39 Diff service kit from FCP Euro.

2 Litres of diff fluid at SCA comes out to $58 (It was a tad more when I compared directly last week, seems to be cheaper now, whatever) versus $53 for the Diff service kit, which includes the plugs. In my existing order, this kit added just $10 to my total shipping cost. Looking at it by itself, the kit, including shipping to Auckland, comes out to $100NZD total. If this is the only thing you're buying, you will probably break even, or maybe even come out a bit ahead buying locally depending on how much them plugs cost. That said, as soon as you stack on some other items into your FCP cart, it'll be extremely cost effective buying from them... It looks like the same exact kit would fit your car too, it's the same diff plug part number, and same oil part number. If it's a $50 shipping cost difference from Auckland to New Plymouth... time to move to the big city! :D

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11 minutes ago, Gabe79 said:

Alright, I have to correct myself a bit. I haven't priced the diff drain/ill plugs locally, so this is an apple to oranges comparison of Penrite diff fluid at SCA versus E39 Diff service kit from FCP Euro.

2 Litres of diff fluid at SCA comes out to $58 (It was a tad more when I compared directly last week, seems to be cheaper now, whatever) versus $53 for the Diff service kit, which includes the plugs. In my existing order, this kit added just $10 to my total shipping cost. Looking at it by itself, the kit, including shipping to Auckland, comes out to $100NZD total. If this is the only thing you're buying, you will probably break even, or maybe even come out a bit ahead buying locally depending on how much them plugs cost. That said, as soon as you stack on some other items into your FCP cart, it'll be extremely cost effective buying from them... It looks like the same exact kit would fit your car too, it's the same diff plug part number, and same oil part number. If it's a $50 shipping cost difference from Auckland to New Plymouth... time to move to the big city! :D

Ahh right that's the kit you were looking at. Yeah that's the same price shipping to me. Oh well I'm committed to buying local now that I've got half the oil lol. I'll just chuck on a fill plug with my next order from FCP. Not sure on that oil brand though, would rather go with something I know works well. From what I've heard the best for this job are Castrol Syntrax Long Life, Red Line High Performance, AMSOIL Severe Gear, and Royal Purple Max Gear (some debate). In my mind why skimp just to save a few 💲

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2 minutes ago, limepanda said:

Ahh right that's the kit you were looking at. Yeah that's the same price shipping to me. Oh well I'm committed to buying local now that I've got half the oil lol. I'll just chuck on a fill plug with my next order from FCP. Not sure on that oil brand though, would rather go with something I know works well. From what I've heard the best for this job are Castrol Syntrax Long Life, Red Line High Performance, AMSOIL Severe Gear, and Royal Purple Max Gear (some debate). In my mind why skimp just to save a few 💲

Grab the kit with the Red Line oil in it. It's a few bucks more. :)  

Edited by Gabe79

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4 minutes ago, Gabe79 said:

Grab the kit with the Red Line oil in it. It's a few bucks more. :)  

Nice find but the shipping price is a bit more on that kit which makes it $135 NZD for the kit. Much cheaper to buy locally at that stage.

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2 minutes ago, limepanda said:

Nice find but the shipping price is a bit more on that kit which makes it $135 NZD for the kit. Much cheaper to buy locally at that stage.

If you're keen on it, and the shipping is the only thing stopping you, write to them and ask for lower shipping. Say you were looking at the Rowe kit, which has semi-reasonable shipping, and there is no good reason the Red Line kit should cost more... Or, just wait till you're doing an order anyway and chuck it on. It'll add very little to an existing order...

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46 minutes ago, Gabe79 said:

If you're keen on it, and the shipping is the only thing stopping you, write to them and ask for lower shipping. Say you were looking at the Rowe kit, which has semi-reasonable shipping, and there is no good reason the Red Line kit should cost more... Or, just wait till you're doing an order anyway and chuck it on. It'll add very little to an existing order...

I tried that with my last order a few weeks ago and they said they couldn't do anything about it and then it turned up today with a ton of spare space in the box that was way too big for it 😞

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