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5.38s with 37s

hjdca

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Ordered my Dana 513's back in November. Front and the masters got in quick, finally got my eaton for the front yesterday, still waiting on the rear gears.

Dana's website says 16 weeks, hopefully since I ordered mine 8-12 weeks ago I don't have much longer to wait. If I hadn't gotten the front already I might ask them to switch back to 4.88's, but I have a feeling I"ll be happier in the long-run.


Did you/Anyone switch out Diff covers when you changed gears? Say a YT video of a shop that was commenting on how little diff fluid was with the stock covers, and moving to an aftermarket cover to increase capacity and add fins for better cooling was almost necessary with 5.13s and 5.38's.
My understanding with Diff covers is the key is distribution of the oil, not the amount of oil. I went with Metalcoak Nodular Iron diff covers because of the added strength, and the nice round interior for good oil distribution. Even though the Metalcoaks have a higher fill hole and looks like they will hold more fluid, I still fill them with the exact Factory recommended amount. I had the bare nodular iron powder coated in two colors. Note: clean the inside of new covers with brake fluid before installation. I use the Mopar fluid recommended for towing, which is the 75w x 140 in both diffs. I have had my Dana 5:13s in for about 33K miles now and I have had zero issues. I have changed the diff. fluid 3 times since I put in the Dana 5:13s. Note: I live in hot weather, over 100 degrees many times in the summer, and mild winters in So. Cal. ..

Jeep Gladiator 5.38s with 37s 9pDFQt




Jeep Gladiator 5.38s with 37s gUogMP
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TheRealGinjaNinja

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Regarding dr
My understanding with Diff covers is the key is distribution of the oil, not the amount of oil. I went with Metalcoak Nodular Iron diff covers because of the added strength, and the nice round interior for good oil distribution. Even though the Metalcoaks have a higher fill hole and looks like they will hold more fluid, I still fill them with the exact Factory recommended amount. I had the bare nodular iron powder coated in two colors. Note: clean the inside of new covers with brake fluid before installation. I use the Mopar fluid recommended for towing, which is the 75w x 140 in both diffs. I have had my Dana 5:13s in for about 33K miles now and I have had zero issues. I have changed the diff. fluid 3 times since I put in the Dana 5:13s. Note: I live in hot weather, over 100 degrees many times in the summer, and mild winters in So. Cal. ..

Jeep Gladiator 5.38s with 37s gUogMP



Jeep Gladiator 5.38s with 37s {filename}
Those look great! Appreciate the info on this!
 

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Panthers65

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My understanding with Diff covers is the key is distribution of the oil, not the amount of oil. I went with Metalcoak Nodular Iron diff covers because of the added strength, and the nice round interior for good oil distribution. Even though the Metalcoaks have a higher fill hole and looks like they will hold more fluid, I still fill them with the exact Factory recommended amount. I had the bare nodular iron powder coated in two colors. Note: clean the inside of new covers with brake fluid before installation. I use the Mopar fluid recommended for towing, which is the 75w x 140 in both diffs. I have had my Dana 5:13s in for about 33K miles now and I have had zero issues. I have changed the diff. fluid 3 times since I put in the Dana 5:13s. Note: I live in hot weather, over 100 degrees many times in the summer, and mild winters in So. Cal. ..

Jeep Gladiator 5.38s with 37s EA9F3375-7807-4E42-913D-51F710DA481D



Jeep Gladiator 5.38s with 37s {filename}
Those look good. I'm using the dana gears and will probably end up going with the dana Advantek covers too. They have the Fins that should help with cooling, and once my final ring gear ships I should be getting a $150 gift card to Northridge from their black Friday deal.

I've never felt like you could put too much fluid in the diff as long as it has some room to move around, I'm planning on filling it up.
 

BearDog

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You guys in Texas are regularly going 85-90+mph on flat highways so something to consider. If 40s are happening I wouldn’t hesitate with 5.38s. What tire you running now?
Running 37's now. 8th gear is a unicorn. 7th visits only once in a while. 40's will definitely need the 5.38's. Think I'll just go with that.
 
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TheRealGinjaNinja

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Running 37's now. 8th gear is a unicorn. 7th visits only once in a while. 40's will definitely need the 5.38's. Think I'll just go with that.
Mine will pull a small grade in 8th from around 70mph+ You are already running 37s so I wouldn’t hesitate to go 5.38s. 85 mph on 37s may be a bit much but at 80 it’s comfortable and not straining. I never go much over 77 mph in any of my Jeeps / trucks anyhow so this is perfect.
 

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TheRealGinjaNinja

TheRealGinjaNinja

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Sorry, no 80 MPH comparison. I only run that fast running from the cops
Awesome thanks for posting comparison pics!! And yea, I never drive 80 either but did for this lol.

These look really close actually. Angle of camera could influence this a bit but reality is 5.38 and 5.13 are not too different. Realistically something like 100-150 rpms. There may be a slight difference in actual tire size here too.

Thanks again for posting these !

Cheers
 

WK2JT

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Awesome thanks for posting comparison pics!! And yea, I never drive 80 either but did for this lol.

These look really close actually. Angle of camera could influence this a bit but reality is 5.38 and 5.13 are not too different. Realistically something like 100-150 rpms. There may be a slight difference in actual tire size here too.

Thanks again for posting these !

Cheers
Yeah, I was thinking that too as I compared. A couple of them looked identical. Also, my ridge grapplers are about halfway through their life. They were put on around 2K miles.

This has definitely given me some food for thought. I might just buy the Mopar crate D44 with 5.13’s and call it a day. The front axle was the worst. Had a shop here in Denver correct them as best they could. The front carrier literally fell out after taking the bearing cap bolts off. They didn’t even need to spread the housing.
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