Foam in Rear Differential - change fluid?

[claluja]

Had a pinion seal leak in my 2014 F250 6.7L. Upon recognizing the leak, when I opened the plug to top off the rear differential fluid a few weeks ago, foam came out. Pretty foamy. Assuming it foamed because rear differential fluid was low and it overheated when towing heavy? It was about 3/4 quart low, with Amsoil SG 75w140 in there. Rear differential holds 3.5 quarts total.

Replaced the pinion seal this weekend, and the fluid that came out during the seal replacement process looked good. Clean and no foam. After replacing the pinion seal, topped her off with another 3/4 quart SG 75w140.

My question is whether I should now replace all the rear differential fluid (don't really want to!)?? What is the chance it was degraded during the low level foamy period? Thoughts? Thanks . . .

 

[Leo99]

Why not change it? Get a cheap pump and it's real easy to pump the fluid in. https://www.amazon.com/dp/B07CX4XKF...d_r=02287ba8-dcbc-11e8-b8fd-f12347a75826

 

[claluja]

Originally Posted by Leo99
Why not change it? Get a cheap pump and it's real easy to pump the fluid in. https://www.amazon.com/dp/B07CX4XKF...d_r=02287ba8-dcbc-11e8-b8fd-f12347a75826


I should've mentioned that changing the fluid in this differential is a pita - there is no drain plug - will need a new lube locker gasket, probably some scraping, etc. So . . . I don't really want to change it, unless there is a reasonable chance the fluid was degraded.

 

[spasm3]

I would change it. A complete rear end rebuild with bearings and posi can be $1300 or so. If you don't and it starts whining later, you will wish you had. If you can change a pinion seal, the rear cover should be no problem. Plus you can look for and large bits of metal and check the gears for wear.

Change it. The foam also could mean water got in there somehow.

 

[CT8]

Felpro makes a gasket for the rear end that makes the oil change much easier.

 

[Trav]

My question is, is this the original diff cover or an aftermarket?

 

[Nick1994]

How many miles? Might still be under powertrain warranty

 

[zeng]

Originally Posted by claluja
Replaced the pinion seal this weekend, and the fluid that came out during the seal replacement process looked good. Clean and no foam. . . .

..... and it's SG synthetic from Amsoil,
just keep going and shortening OCI to 70-80% of OEM recommendation.
Degradation, if any appears to be of no significance.

 

[claluja]

Originally Posted by Trav
My question is, is this the original diff cover or an aftermarket?


Original diff cover. Lube locker gasket currently in there. Truck has about 145K on her, and diff fluid was last changed at 93K.

P.S. injectors look great. Thanks!

 

[Trav]

Good, at least its from running a little low and not due to an aftermarket cover most of which tend to induce foaming. Yes I would change it, running low may have sheared it down.
Glad you like the injectors, they came out great.

 

[GenesisGuy70]

Given the cost of a replacement hardware, I don't think I'd be able to sleep if I didn't change it. It would be a shame to drop that fresh Amsoil though. I don't know, tough choice.

 

[StevieC]

I'd change the fluid and while you are in there add a cover that has a drain plug. But keep the stock type design don't go for a deeper pan or square pan etc. As per the videos recently posted here as to why.

 

[Trav]

What video? I rarely read your post anymore because of all the mostly useless videos.

 

[StevieC]

Originally Posted by Trav
What video? I rarely read your post anymore because of all the mostly useless videos.

They weren't my videos they were posted by another user.

https://www.youtube.com/watch?v=n4DQ-jzKQRw
https://www.youtube.com/watch?v=09JsDorR6tw
https://www.youtube.com/watch?v=9-yG3D3JBRs

 

[Trav]

Hey no offense but its getting crazy with the videos and not just you. If I wanted to watch you tube I would.

 

[StevieC]

Originally Posted by Trav
Hey no offense but its getting crazy with the videos and not just you. If I wanted to watch you tube I would.

No one is forcing you to watch them. This is a forum for discussion and the video might set that discussion up.

 

[HorseThief]

Jeez.... What a giant gaping a-hole. You don't have to read the threads or watch the videos. It's not like there's a finite amount of internets to go around. You also don't have to respond so harshly. If all you want to do is crap all over somebody, you really should be on YouTube - you'd fit in perfectly with the commenters over there. Trev, I know you've been here a while and have over 20k posts but you're still being a [censored] for no good reason.

 

[tcp71]

Even clean differential oil gets pretty frothy during use...I wouldn't let it worry me. A video can show a lot.

 

[claluja]

Thanks for the comments guys. Ordered a new lube locker gasket today, and planning to change the fluid when it arrives.

Sticking with stock cover. Don't want to worry about flow paths, and I'm guessing I may not have noticed my pinion seal leak if I had a fancy cover on there. Also, no need to give Johnny Law an express invitation to look under my truck.