added .5 litre of synthetic 75-90 gear oil to my diff

[bluebombersfan]

I noticed a leak coming from my diff where the drive shaft enters. I added .5 litres to top it off. Not sure how long I have been driving like this. I think it takes 2.5 litres so I'm hoping nothing has been damaged with 1/2 litre low oil.

The thing is in my panic I added 75-90 synthetic gear oil to top it off. I think my truck calls for 80-90. I don't know much about diffs but I would assume that this would not be much of a problem especially with a small amount.

I hope to get a new seal installed this week. I have lots of driving to do though till then but I figure I can keep an eye out on the oil level in my diff for now.

 

[shane96ranger]

I wouldn't chance it. Mixing fluid types is not recommended. I would get it all changed.

Sent from the can

 

[alwaysFlOoReD]

I mix oil types and weights all the time. AFAIK there is no problem mixing dino and synthetic, the manufacturers do it. And I've be mixing winter weights to get an acceptable - to me - weight of 7.5w/40 in my 2004 f-150. Stock is 5w/20. It has a problem with the gasket or seal for the cam phazers and that's how I saved myself a $3500.00 engine repair.

Richard

 

[bluebombersfan]

I mix engine oils all the time but I asked the question because I don't know anything about diff fluids. I actually use a mixture of half 5w30 and half 5w20 for my ranger, but like I said I didn't ever know much about diff fluids.

 

[Frank The Tank]

I prefer to run full synthetic for heat dissipation but it doesn't hurt my feelings to mix them just for a top of or something.

 

[shane96ranger]

This explanation in an old thread of mine is good enough for me. I never question Alan.

It is critically important when you see that tag "75W140 synthetic only" to go to the ford dealer and use ONLY that oil.

If you want to experience the "Horror" allow that oil to mix with almost any other oil...

It will ALL set up like chocolate pudding.


I've literally seen a quart of that oil cause a full oil pan of cranccase oil ("dino oil")
drained from my 2.9 at the time and three quarts of Mercon2 to set up into "fudge"
that I was able to remove from my oil pan by the handful in chunks and able to wipe my hand oil free with ONE paper towel.

IF you ever desire to change your diff oil to something else I'd strongly recmmend disassembly and steam cleaning (especially inside the tubes) before you put any other kind of oil in that housing.

That being said the Ford 75W140 synthetic is likely the best oil money can buy

(last I checked it was $18 a quart)

Posting whilst sitting upon the throne.

 

[Andy D]

Shane, The OP added a pint of 75 w 90[COLOR="Red" not the Ford stuff.

 

[shane96ranger]

I didn't say He did Andy. That was red from Allan's post that I quoted.

My main objective was the other parts of the post.

Posting whilst sitting upon the throne.

 

[Andy D]

No trouble, I'm a bit slow on the segue some mornings.

 

[alwaysFlOoReD]

Quote:
Originally Posted by AllanD View Post
It is critically important when you see that tag "75W140 synthetic only" to go to the ford dealer and use ONLY that oil.

If you want to experience the "Horror" allow that oil to mix with almost any other oil...

It will ALL set up like chocolate pudding.


I've literally seen a quart of that oil cause a full oil pan of cranccase oil ("dino oil")
drained from my 2.9 at the time and three quarts of Mercon2 to set up into "fudge"
that I was able to remove from my oil pan by the handful in chunks and able to wipe my hand oil free with ONE paper towel.

IF you ever desire to change your diff oil to something else I'd strongly recmmend disassembly and steam cleaning (especially inside the tubes) before you put any other kind of oil in that housing.

That being said the Ford 75W140 synthetic is likely the best oil money can buy

(last I checked it was $18 a quart)

That's interesting. I have great respect for AllanD so I will make sure to not mix 75w/140 synthetic with other oils....
I'm also going to test that someday.

Richard

 

[coral191]

OK, now you guys are scaring me.....2005 Escape 4WD, 130,000 miles...Power Transfer Unit (front gear box) calls for Ford 75W-140 Synthetic. I recently drained it until it quit dripping, and refilled with Mobile 1 75W-140 Synthetic. (because I use Mobile 1 Synthetic in most places)

Problem??????

 

[alwaysFlOoReD]

Problem????
I really doubt it. You can do some research at bobistheoilguy.com
Off subject; I found an interesting nugget of info;

For example, the chart indicates that an SAE 50 engine oil and an SAE 90 gear oil are the same viscosity. This might surprise you if you think that gear oil is always thicker than engine oil. However, as Table 5 shows, they are nearly equivalent.

Richard

 

[shane96ranger]

OK, now you guys are scaring me.....2005 Escape 4WD, 130,000 miles...Power Transfer Unit (front gear box) calls for Ford 75W-140 Synthetic. I recently drained it until it quit dripping, and refilled with Mobile 1 75W-140 Synthetic. (because I use Mobile 1 Synthetic in most places)

Problem??????

You'll be fine there. I used Valvoline (my brand of choice when not using Motorcraft) in my F150 and it's been in there for a year.