How many of you run a Mag-Hytec diff cover?

to this point, I know ford released a finned alum diff cover for the 10.5 sterling in like 2008? I know they currently dont put these on new truck to my knowledge. Just an interesting fact.
 
to this point, I know ford released a finned alum diff cover for the 10.5 sterling in like 2008? I know they currently dont put these on new truck to my knowledge. Just an interesting fact.
2008-2011 got them I believe. They look cool. I would run one, but not worth swapping the gear oil for since all I do is drive around town looking at all the things I can't fit in my shortbed truck.
 
I need to watch those videos when I get out of airport purgatory. Sounds like my kind of party.

I don't really know anything about towing big stuff, but I like nerdy videos.

(Showing my ignorance) Why not run a small external cooler and a fluid pump? Are temps only marginally high, so more fluid and a finned cover is all it takes to solve the problem? The cover is obviously an easy and relatively cheap upgrade compared to a pump and cooler, so if that's all you need...?
 
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Gotta keep it as simple as possible. Simple usually means affordable.
 
I just want to know which one drops the temperature more. Adding capacity without shedding heat would just mean you have a larger capacity of "hot" oil.

But merely "heating" the oil isnt a problem. Now heating beyond its limits, sure. I think thats where we need to start. Is there data to prove that failures are caused by gear oil thermal breakdown?

I expect not, at least in all but the most extreme cases...in fact if it's getting that hot I'd almost immediately question r&p set up.
 
Is there data to prove that failures are caused by gear oil thermal breakdown?

If you overheat the gear oil, and it stops acting like gear oil, would it not cause failures....?

R&P setup is one cause of overheating, but applying a lot of load/power versus time is another (towing, or race cars).
 
If you overheat the gear oil, and it stops acting like gear oil, would it not cause failures....?

R&P setup is one cause of overheating, but applying a lot of load/power versus time is another (towing, or race cars).


No I get that. I totally do.
My question was, are all these high dollar dif covers solving a problem that actually exists, or are they solving a strawman that advertisers created.

How many new 1 ton rear ends are failing at all? And of the ones failing, how many are failing because of oil thermal breakdown? (as opposed to water intrusion, shock loading, improper maintenance, improper factory fill, poor initial setup, etc.)
 
No I get that. I totally do.
My question was, are all these high dollar dif covers solving a problem that actually exists, or are they solving a strawman that advertisers created.

How many new 1 ton rear ends are failing at all? And of the ones failing, how many are failing because of oil thermal breakdown? (as opposed to water intrusion, shock loading, improper maintenance, improper factory fill, poor initial setup, etc.)

That was sort of my question too; Is the problem that bad if a finned cover and some extra fluid is the accepted solution...?

I can see if you're pushing 220-240degF fluid temp or whatever, and the finned cover lowers the temp 5-10 degrees and gives some extra safety margin, but if you're actually getting too close to the max fluid temp then you would need a real cooling solution and not an incremental temp reduction.

What kind of fluid temps are people actually seeing that get these covers? Again, I'm just thinking out loud because I'm just learning about this stuff.
 
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This is why I wish they'd get the next video out. I want to see some numbers.
 
No I get that. I totally do.
My question was, are all these high dollar dif covers solving a problem that actually exists, or are they solving a strawman that advertisers created.

How many new 1 ton rear ends are failing at all? And of the ones failing, how many are failing because of oil thermal breakdown? (as opposed to water intrusion, shock loading, improper maintenance, improper factory fill, poor initial setup, etc.)
No, I just think it another well, you know, it's gotta be better thing......blah blah blah here's something else to throw your money at.

I mean it's really to me not any different then a new filter thingy, or exhaust, or or or..and so on. Its just not plainly adding any real benefit other than lookey lookey at my big ol' fancied up rear end. Truck nuts, stupid wheels, and enormous diff covers all fall in the same category for me. Diff covers just have a seemingly bettering your truck sales pitch. Bogus or not it's still not needed.
 
No, I just think it another well, you know, it's gotta be better thing......blah blah blah here's something else to throw your money at.

I mean it's really to me not any different then a new filter thingy, or exhaust, or or or..and so on. Its just not plainly adding any real benefit other than lookey lookey at my big ol' fancied up rear end. Truck nuts, stupid wheels, and enormous diff covers all fall in the same category for me. Diff covers just have a seemingly bettering your truck sales pitch. Bogus or not it's still not needed.

I wanna agree with you and argue with you at the same time. I read online (I know, gotta be true) that people were shooting rear diffs with an infrared temp gun and seeing 40+ degree drops in temp from installing the Mag Hytec covers. Although not many people have reported rear end failures, I tend to think that cooler is better and offers longevity to internal parts. Also, out of the covers being tested, Mag Hytec is the one that’s more form over bling. As in no big fancy letters or glaring brand name molded in.
 
Was the temp drop measured by fluid temp or case/cover temp?
That makes a difference...

What I read was shooting the diff cover itself. No way of knowing fluid temp without using an actual probe.
 
So after watching the videos (and without seeing the 3rd part), it seems like the solution to making something functional and aesthetically desirable would be to make a finned aluminum cover with a proper inner flow path along the inside surface. I would think some kind of de-aerating baffle would be helpful too, but I don't know if that would actually work given the fluid motion and lack of space. If extra capacity is needed, a deeper cover that still has a proper flow path (even a stamped sheet metal half-banana inside a cast cover) could maybe work as well.

This is fun, even though this type of product is completely useless for my personal needs.
 
So, something like.... a diff cover with an air scoop that directed air across some fins? I can dig it.
 
So, something like.... a diff cover with an air scoop that directed air across some fins? I can dig it.

Doing a scoop or duct would actually be really easy. It could be sheet metal or fiberglass or molded plastic, and could just fasten to one of the axle tubes with hose clamps or whatever. There would be a drag penalty, as there always is, but it probably wouldn't take much to clean up flow around the diff cover so the amount of air needed would probably be low. I don't think a scoop/duct would be needed though, because it sounds like there are easy gains in other places for a proper cover design before worrying about cooling airflow.

It's fun to be a spectator (armchair engineer?) on someone else's engineering project.
 
What I read was shooting the diff cover itself. No way of knowing fluid temp without using an actual probe.
Jody posted what I was going to as I read through.
So the video's prove that the cooling fins and pretty cover effectively cool the outside of the diff cover. They do nothing to show the effect on internal fluid temps.

Even still the fluid has an operating temp range. For shits and giggles lets just assume the optimal operating range is 180-220F. Maybe cooler than that its too viscous to sling and spread properly and above that it starts to break down. If the fluid is running at 240F, agree we have a problem and we need to fix it. However if the fluid is running at 208 and the cover drops it to 190 (in my mythical example) you have provided zero benefit.
 
Jody posted what I was going to as I read through.
So the video's prove that the cooling fins and pretty cover effectively cool the outside of the diff cover. They do nothing to show the effect on internal fluid temps.

Even still the fluid has an operating temp range. For shits and giggles lets just assume the optimal operating range is 180-220F. Maybe cooler than that its too viscous to sling and spread properly and above that it starts to break down. If the fluid is running at 240F, agree we have a problem and we need to fix it. However if the fluid is running at 208 and the cover drops it to 190 (in my mythical example) you have provided zero benefit.
exactly.....gear lube and all the other is designed to operate along a temperature span. Like you said previously failures have to be prone to outside sources or lack of maintenance. No manufacturer in their right mind would engineer a diff and related to over heat and break down the fluid. As for loading, well that's in the owners manual as well. Got 350 and need to pull 36k? Your diff cover is the least of your worries.
 
I'll just keep my OEM finned diff cover for my in warranty truck.

In my 18 years at a dealership (16 as a certified gear tech) I saw maybe a handful of R&P failures due to overheating on a stock vehicle.
The majority of issues was from poor/improper initial assembly at the axle manufacturer plant when they were running multiple shifts of warm bodies just to meet Jeep market demand.
i.e.- Betty Sue, Jose and Wilma assembling D44a on third shift when Dana needed to meet quotas to keep up with Grand Cherokee sales volume.
 
I'll just keep my OEM finned diff cover for my in warranty truck.

In my 18 years at a dealership (16 as a certified gear tech) I saw maybe a handful of R&P failures due to overheating on a stock vehicle.
The majority of issues was from poor/improper initial assembly at the axle manufacturer plant when they were running multiple shifts of warm bodies just to meet Jeep market demand.
i.e.- Betty Sue, Jose and Wilma assembling D44a on third shift when Dana needed to meet quotas to keep up with Grand Cherokee sales volume.
You would imagine an aluminum housing of the D44a would dissipate the heat better than a cast iron housing too...
 
I did use the D44a just as an example. When Chrysler was having an abundance of differential issues in the late 90s to early 2000s, it was attributed to poor build quality at the axle manufacturing plants. According to our Chrysler instructors anyway.
This applied to all Dana axles especially those in the ZJ/WJ line as the unibody construction did very little to reduce noise compared to body on frame applications.
 
You would imagine an aluminum housing of the D44a would dissipate the heat better than a cast iron housing too...
It does. Too bad the pattern changes and the bearings spin due to deflection.
 
A little behind the scenes about this

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