Differential?

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Mar 30, 2011 | 03:44 PM

#16

Moto Mel

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From: Chesapeake, Va.

Yup, that is really good information and maybe the Moderators could make a sticky of it.

Mar 30, 2011 | 04:06 PM

#17

jwhopson

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Tuned

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From: McMinnville

So with limited slip does that mean I should have added the "additive" to the gear oil in the rear differential?

Mar 30, 2011 | 04:20 PM

#18

Moto Mel

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From: Chesapeake, Va.

In a word, yes. Without the additive the clutches will not work as engineered by Ford. Not a big deal to add the modifier, just remember to put it in first and then the gear lube so you don't have to remove some lube afterwards to finish the job.

Mar 31, 2011 | 10:57 PM

#19

jwhopson

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Tuned

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From: McMinnville

Thank you for your help. I looked at Redline 75/140 and it says it contains the friction modifiers so no additional is needed. Any experience with this. This truck will continue a hard life for another year+ so I have to be very kind.

Red Line Synthetic Oil - Gear Oil for Differentials - 75W140 GL-5 Gear Oil

Any suggestions for oil in the front differential (it has 8.8 stamped on the cover) but couldn't find in the manual under the specs. I wish they had a tag on the front like the one on the back -- why be inconsistent.

Apr 1, 2011 | 02:37 PM

#20

Moto Mel

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From: Chesapeake, Va.

Quote:

Originally Posted by jwhopson

The Red Line gear oil should be fine for the rear. You will need 75W90 lube for the front according to my owner's manual on page 197.

Ford is, at times, very consistent only in their inconsistancy. We learn to expect it and live with it after a while.

Apr 6, 2011 | 07:56 PM

#21

jwhopson

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From: McMinnville

Yahoo. I did it. Thank you to everyone who provided support and confidence. I ended up using Amsoil with the non-slip additive. I am hoping that I put the correct amount - I used the manual although it's not a very good one. Regardless I think I will tackle the transmission next and see if it is easy to drain the TC - although I am unclear how it turns to get it lined up - but I am sure there are threads of how to....

Again thank you all!!

Apr 6, 2011 | 09:49 PM

#22

Moto Mel

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From: Chesapeake, Va.

Quote:

Originally Posted by jwhopson

Easy job, just remove the black plug under the T/C, rotate the engine til the little bolt looking thing is at the bottom and remove it , let the fluid drain into the drain pan while you drop the trans pan and replace the filter, You reuse the pan gasket. Refill, with about 6 qts and start the engine and keep adding fluid while checking the level often until full.

Apr 7, 2011 | 07:22 AM

#23

cdherman

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From: Parkville, MO (KC)

Ford now puts the synthetic 75w140 in front differentials too, even if they called for 70w90 originally. Ford parts guy showed me right in the ford desk book.

Really, when you think about what those numbers mean, you will understand. The second number, 90, means that at 200 degrees (hot) the oil behaves like 90 weight. The first number, 70, is the cold viscosity, number.

Now, the full synthetic oil, behaves likes 140 weight oil at 200 degrees. On first blush you might say, OMG that is too heavy, but remember, 140 weight oil at 200 degrees is FAR thinner than 70 weight oil at zero....

I don't know if all that makes sense, but me, I would put the synthetic in there....