Accidentally mixed 75-90 diff fluid with 75-140

[Wajeep]

Changed Rear diff fluid on my Ford 8.8 rear axle. Noticed that I accidentally added a couple of quarts of 75-140 with the 2qts of 75-90. Is this ok?

 

[Brianj5600]

No problem, now you have 75-115. Did you put 4 quarts in it?

 

[steelhd]

You need a whole lot less lube than 4 quarts.

 

[Wajeep]

No problem, now you have 75-115. Did you put 4 quarts in it?

Yep. I think 2 of each. Bottles are identical except for oil weight and next to each other on the shelf. I’ll pay closer attention.

You need a whole lot less lube than 4 quarts.

that’s when it started coming out of the fill plug.

 

[Jerry Bransford]

No problem whatsoever. As above you just now have 75W-115 which is actually a nice viscosity.

 

[Wajeep]

No problem whatsoever. As above you just now have 75W-115 which is actually a nice viscosity.

Thanks Jerry!

 

[Rubicon88]

Perfectly A OK!!!

 

[LJBean]

Do you have stock diff covers? Some aftermarket covers have the fill hole higher to compensate for raised pinions. You'll know if you overfilled the diff when gear lube shoots out your breather and gets all over the back of your jeep.

 

[Cross-Threaded-06TJ]

The fill plug for his 8.8 is up by the Pinion cast into the housing. Also his pinion is probably tipped up because his Jeep is lifted.

OP your Good to go, and the 8.8 holds around 4 quarts when tipped up, the tubes are bigger than a dana 44 or 35 that some are used to.

I had an 8.8 I swapped into my YJ years ago, it held a lot.

 

[LJBean]

Ah - not too familiar with the 8.8, though I know it's a popular swap. Thanks for the clarification.

 

[Wajeep]

The fill plug for his 8.8 is up by the Pinion cast into the housing. Also his pinion is probably tipped up because his Jeep is lifted.

OP your Good to go, and the 8.8 holds around 4 quarts when tipped up, the tubes are bigger than a dana 44 or 35 that some are used to.

I had an 8.8 I swapped into my YJ years ago, it held a lot.

Thanks for the help!