XF Coupe - Rear Diff Oil ?
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Joined: May 2012
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From: Southampton Hants
XF Coupe - Rear Diff Oil ?
Gents,
Xfire Coupe UK......
What Oil is recomended for the rear axle, and is there anything that any one recomends instead or cheaper ?
Regards
Grant B
Xfire Coupe UK......
What Oil is recomended for the rear axle, and is there anything that any one recomends instead or cheaper ?
Regards
Grant B
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From: Orlando, FL
Re: XF Coupe - Rear Diff Oil ?
I've had great luck with the AMOIL Severe Gear 75w-90. I guess it works well because I've drag raced over 500 times and still have the original rear end. 
Last edited by Mimi05SRT6; May 29, 2012 at 03:24 PM.
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From: Durham, NC
Re: XF Coupe - Rear Diff Oil ?
Well I am going out on a limb here and guessing AMOIL ATF is auto trans oil. Probably designed for use in...you guessed it Automatic transmissions. Personally I would probably gargle with it before I put it in my rear end but I don't race. Use a gear oil. Synthetic.
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From: Ontario
Re: XF Coupe - Rear Diff Oil ?
SAE Synthetic 75W-140
API GL-5
ATF is a bit thin if you ask me. I think the need is for an oil that can withstand high pressure between mating faces.
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From: Durham, NC
Re: XF Coupe - Rear Diff Oil ?
2005 Chrysler Crossfire Mercedes Gear Oil, Hypoid SAE 85W-90, Spec 235.7 001 989 17 03 10
The following material data sheet is interesting as in the beginning it refers to BP which I assume is British Petrolium and at the end of the sheet it states that it is a
Mobile document.
http://images.imcparts.net/shared/do...1989170310.pdf
The following material data sheet is interesting as in the beginning it refers to BP which I assume is British Petrolium and at the end of the sheet it states that it is a
Mobile document.
http://images.imcparts.net/shared/do...1989170310.pdf
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From: Kellyville, Ok
Re: XF Coupe - Rear Diff Oil ?
Yep.. tells me less than two hours run time and cool downs in between.. unless this is a daily driver too..
Thread Starter
Joined: May 2012
Posts: 200
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From: Southampton Hants
Re: XF Coupe - Rear Diff Oil ?
Owners Manual says.
SAE Synthetic 75W-140
API GL-5
ATF is a bit thin if you ask me. I think the need is for an oil that can withstand high pressure between mating faces.
Re above, 75w - 140 is quite a high pressure oil, but wondering why it's thin ???
I understand the diffs on these XCF's are a limited slip diff.... if so, do they need a thinner oil to operate ?
most vehicles have a diff oil of EP 75 > 90...., so this one rated at 140 at high temp is good, but im wondering why it is so watery ???
I've used alternative oils to manufactureres recomended before and come a cropper & destroyed axles and gearboxes thinking I knew better .....
But I'm wondering at the logic of this ATF fluid in a rear axle . . . . unless it needs a thin oils for the diff lock to work ???
saying that, My landrover descovery uses a special ATF fluid in its main transmission manual box.....
But anything else simply was too thick and you couldnt change gear and the synchro simply would not allow u to change gear let alone put it in gear, and other oils would destroy a box in 5,000 miles totally.
Penny for your thoughts ??
Regards to all.
Grant B
SAE Synthetic 75W-140
API GL-5
ATF is a bit thin if you ask me. I think the need is for an oil that can withstand high pressure between mating faces.
Re above, 75w - 140 is quite a high pressure oil, but wondering why it's thin ???
I understand the diffs on these XCF's are a limited slip diff.... if so, do they need a thinner oil to operate ?
most vehicles have a diff oil of EP 75 > 90...., so this one rated at 140 at high temp is good, but im wondering why it is so watery ???
I've used alternative oils to manufactureres recomended before and come a cropper & destroyed axles and gearboxes thinking I knew better .....
But I'm wondering at the logic of this ATF fluid in a rear axle . . . . unless it needs a thin oils for the diff lock to work ???
saying that, My landrover descovery uses a special ATF fluid in its main transmission manual box.....
But anything else simply was too thick and you couldnt change gear and the synchro simply would not allow u to change gear let alone put it in gear, and other oils would destroy a box in 5,000 miles totally.
Penny for your thoughts ??
Regards to all.
Grant B
Senior Member
Joined: Apr 2006
Posts: 25,432
Likes: 648
From: Ontario
Re: XF Coupe - Rear Diff Oil ?
Owners Manual says.
SAE Synthetic 75W-140
API GL-5
ATF is a bit thin if you ask me. I think the need is for an oil that can withstand high pressure between mating faces.
Re above, 75w - 140 is quite a high pressure oil, but wondering why it's thin ???
I understand the diffs on these XCF's are a limited slip diff.... if so, do they need a thinner oil to operate ?
most vehicles have a diff oil of EP 75 > 90...., so this one rated at 140 at high temp is good, but im wondering why it is so watery ???
I've used alternative oils to manufactureres recomended before and come a cropper & destroyed axles and gearboxes thinking I knew better .....
But I'm wondering at the logic of this ATF fluid in a rear axle . . . . unless it needs a thin oils for the diff lock to work ???
saying that, My landrover descovery uses a special ATF fluid in its main transmission manual box.....
But anything else simply was too thick and you couldnt change gear and the synchro simply would not allow u to change gear let alone put it in gear, and other oils would destroy a box in 5,000 miles totally.
Penny for your thoughts ??
Regards to all.
Grant B
SAE Synthetic 75W-140
API GL-5
ATF is a bit thin if you ask me. I think the need is for an oil that can withstand high pressure between mating faces.
Re above, 75w - 140 is quite a high pressure oil, but wondering why it's thin ???
I understand the diffs on these XCF's are a limited slip diff.... if so, do they need a thinner oil to operate ?
most vehicles have a diff oil of EP 75 > 90...., so this one rated at 140 at high temp is good, but im wondering why it is so watery ???
I've used alternative oils to manufactureres recomended before and come a cropper & destroyed axles and gearboxes thinking I knew better .....
But I'm wondering at the logic of this ATF fluid in a rear axle . . . . unless it needs a thin oils for the diff lock to work ???
saying that, My landrover descovery uses a special ATF fluid in its main transmission manual box.....
But anything else simply was too thick and you couldnt change gear and the synchro simply would not allow u to change gear let alone put it in gear, and other oils would destroy a box in 5,000 miles totally.
Penny for your thoughts ??
Regards to all.
Grant B
The OEM diffs are not limited slip.
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From: Orlando, FL
Re: XF Coupe - Rear Diff Oil ?
Last edited by Mimi05SRT6; May 29, 2012 at 03:25 PM.
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From: IN
Re: XF Coupe - Rear Diff Oil ?
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From: Georgia
Re: XF Coupe - Rear Diff Oil ?
I changed my rear diff oil first at 47,000 miles with mobile 1 75-140 (it was burnt!). I just changed it for a second time at 67,000 miles with royal purple 75-140 (not as burnt as the first time)... the royal purple seems to have toned down the rear end "whine" these diffs are known for.
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Posts: 9,595
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From: Kellyville, Ok
Re: XF Coupe - Rear Diff Oil ?
I changed my rear diff oil first at 47,000 miles with mobile 1 75-140 (it was burnt!). I just changed it for a second time at 67,000 miles with royal purple 75-140 (not as burnt as the first time)... the royal purple seems to have toned down the rear end "whine" these diffs are known for.
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From: SAN ANTONIO, TEXAS
Re: XF Coupe - Rear Diff Oil ?
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From: Vancouver BC Canada
So no Additional friction modifier is required is that correct?
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From: Rochester Hills, MI
Re: XF Coupe - Rear Diff Oil ?
My owner's manual calls for 75w-85, so, like Mimi, I've used Amsoil 75w-90. Did I miss the memo on 75w-140 for the diff in my '07 NA?
Last edited by harbor; Apr 29, 2013 at 06:22 PM.