Cooling Differential covers, do they really matter?

[bhgl]

Howdy folks!

I just recently saw an ad for Banks Ram Air Differential covers and I was pretty intrigued, apparently they do actually lower differential temperatures. My truck has a limited slip 7.5 rear end, and of course Banks doesn't make these for the Ford 7.5, or even the 8.8. It did get me thinking however if aftermarket covers really do offer cooling advantage. Seems like most people who attest to these do some capital T TOWING.

I don't really tow, but I do drive very quickly for long periods of time and long distances, I'd like to keep my original diff and its clutch material healthy for as long as possible, and I'm wondering if an aftermarket diff cover would help in that regard.

What do you guys think?

 

[Blmpkn]

Cost/benefit in your case.. light-years from worth it IMO. I'd wager that your truck could probably be run at redline in top gear all day long and not create enough heat to bother anything over the reccomended OCI

 

[ekrampitzjr]

The aftermarket cover probably can't really harm anything. But my suspicion is that if finned diff covers made a real difference, you'd see them from the factory as part of a "heavy duty" or "towing" package. If the diff is somehow heating up so much that the fins get hot, you've got problems brewing anyway.

 

[bhgl]

Cost/benefit in your case.. light-years from worth it IMO. I'd wager that your truck could probably be run at redline in top gear all day long and not create enough heat to bother anything over the reccomended OCI

That's what I figured, although some other aftermarket covers do have extra capacity for fluid which would be kinda nice to have.

Either way, I'm not spending 500$ on a thick piece of metal.

 

[Uncle Gump]

Ford 7.5, Straight Fins

Check out the deal on Ford 7.5, Straight Fins at PML YourCovers.com

yourcovers.com

 

[bhgl]

The aftermarket cover probably can't really harm anything. But my suspicion is that if finned diff covers made a real difference, you'd see them from the factory as part of a "heavy duty" or "towing" package. If the diff is somehow heating up so much that the fins get hot, you've got problems brewing anyway.

I know on some of the newer RAM 3500s they've used some bigger diff covers to hold more fluid.

On some of the high performance mustangs and corvettes they've used cooled differential with lines that go to a heatsink.

I'm sure it's something to consider for high performance, heavy duty applications, the question is how much does it matter in a lil ford ranger.

 

[Blmpkn]

Either way, I'm not spending 500$ on a thick piece of metal.

Not even if it says BANKS on it?

On the topic of additional capacity covers though, again.. probably unnecessary in your case. The extra fluid WOULD allow you to run a longer OCI.. which Is nice.. but with how cheap it is to fill a 7.5.. it would probably take a half million miles (at least) to recoup the cost of the cover.

More or less.. functionally worth it? No. Aesthetically worth it? That's up to you. Fancy covers DO certainly add a bit of flare to an otherwise boring looking hunk of steel I may end up with one for my ranger just for that reason.. mabey.. I'm planning on lowering it though so the only time anyone would see it.. it would only be by ME and only when I have it up in the air

 

[Lefty]

I recently had installed a new limited slip. I asked the transmission shop about a new cover. They said any would do. So I bought this for $40.00.

 

[bhgl]

I recently had installed a new limited slip. I asked the transmission shop about a new cover. They said any would do. So I bought this for $40.00.

I wanna say that looks like a stock 8.8 cover but since it's so shiney I can't tell?

 

[racsan]

Years ago I bought a summit alloy cover (for a 8.8 though) still have it, bought it for the drain & fill plugs, added bonus is that it holds more oil. I still have it-somewhere.
I doubt your truck would generate enough differential heat to be a issue- unless it was very low on oil, Then you’d need another axle once it seized up.

 

[Lefty]

I wanna say that looks like a stock 8.8 cover but since it's so shiney I can't tell?

Yes, 8.8.

All cars and trucks seem to have their fair share of issues, but differential covers are not one of them: not unless they leak. A couple people here have suggested an oil change after 150,000. Still it seems that most go much longer.

 

[sgtsandman]

RWD based vehicles of various brands have run for hundreds of thousands of miles with just the factory cover. Changing the fluid in the axle on a regular basis and often times, more often than the manufacturer recomends is more critical.

If you do decide to upgrade to a "better" cover, the video that Banks did on coming up with that very cover is food for thought.

Thus why I went with the ARB cover for my trucks. The interior profile follows the factory contour, it has a drain plug, braces differential housing, and will survive an impact way better than the factory cover. Lastly, it looks a heck of a lot better than the factory cover.

Most of that probably doesn't interest you other than perhaps getting a cover with a drain plug in it. You can get a bung welded to a factory cover for way cheaper than what you will pay for most fancy aftermarket covers.

As far as the fluid change interval, different opinions float around on that. If you don't haul a lot, 60,000 miles would be what I would go with. Since I off road and haul with mine, the rear axle gets changed at 30,000 and the front at 60,000 unless I suspect the axle fluid has been contaminated with water and mud.

 

[Lefty]

RWD based vehicles of various brands have run for hundreds of thousands of miles with just the factory cover. Changing the fluid in the axle on a regular basis and often times, more often than the manufacturer recomends is more critical.

If you do decide to upgrade to a "better" cover, the video that Banks did on coming up with that very cover is food for thought.

Thus why I went with the ARB cover for my trucks. The interior profile follows the factory contour, it has a drain plug, braces differential housing, and will survive an impact way better than the factory cover. Lastly, it looks a heck of a lot better than the factory cover.

Most of that probably doesn't interest you other than perhaps getting a cover with a drain plug in it. You can get a bung welded to a factory cover for way cheaper than what you will pay for most fancy aftermarket covers.

As far as the fluid change interval, different opinions float around on that. If you don't haul a lot, 60,000 miles would be what I would go with. Since I off road and haul with mine, the rear axle gets changed at 30,000 and the front at 60,000 unless I suspect the axle fluid has been contaminated with water and mud.

Now we know!

 

[don4331]

Cost/benefit in your case.. light-years from worth it IMO. I'd wager that your truck could probably be run at redline in top gear all day long and not create enough heat to bother anything over the reccomended OCI

In most cases, you probably should have a bigger truck (over GCWR) before you are heating the oil.

It's not top gear at redline towing that is worst case - its towing something so heavy you can't get to top gear that's the issue.​

And yes, I heated the oil in the rear differential of my S-10 to the point the paint pealed (and that was with 4 banger).​

@bhgl also needs to consider that the fins that might be keeping the diferential a few degrees cooler in July, will also be keeping it a few degrees cooler in January (when its -40).

@sgtsandman types faster: Banks that demonstrates that the cover pictured by @Uncle Gump does worse job at cooling then the stock one in @Lefty 's picture as there is some science to the stock one keeping the oil liquid, while the aftermarket one tends to foam the oil and as a result it heats.

 

[Uncle Gump]

Yeah... I read some study and it was also discussed here that the larger capacity covers cool worse... lubricate poorer and also generate more foam then the good old factory cover.

I went with a modular steel cover from Yukon Gear... witch is the same volume but offers more protection if I bump it into something off road. And... it looks cooler.