Locker and 13 bolt shave install.

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Frankenchevy

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I drive my truck from and to the trails. And most of the time I just cruise at around 60- truck seems to like it and I've never had any issues.

But several years ago a trail took me longer than I thought and I had to haul butt back home to pick up my kid from school. So I did an hour of highway driving at 70-75 mph. Screaming along at 3500 RPM made it in time. But when I got out of my truck I smelled oil- my 14 bolt rear diff puked its fluid out of the vent hose attached onto the underside of the bed. Differential was very hot. It has never done this again- but I haven't driven that fast. In fact I drove it to my parents a few weeks ago with a load of firewood on the highway. It's 2.5 hours by highway (at 60 mph) to get there.

Why? Was it the aftermarket thick cover?

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Was it the fact that my exhaust dumps before the axle and maybe all that exhaust was heating it up?

Don't know.
I didn't watch blue ox's video, so I'm not sure what it said. As explained to me, it's not the thickness that's the issue, it's the shape. the stock one is shaped to optimize fluid travel with its round schwoop vs. the geometric shapes they weld the aftermarket ones from. it helps to fling the oil around in the right manner as opposed to throwing it at a wall and having it run back down.
 

77 K20

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I didn't watch the link either (blocked at work) but know there was a video maybe made by Banks? That was talking about the shape of aftermarket diff covers. That they were not smooth to promote nice flow and instead agitate the fluid into a froth and thus it gets hot.

Not sure I buy that idea either. I have an AFE cover on my Silverado and have pulled trailers in the summertime heat for 11 hours at a time. (it is about as square shaped as you can get) It was hot enough all the fluid boiled out of my clutch hose and had to pump the clutch multiple times before it started working again. Never had my rear diff fluid puke out or have had it get too hot. I have an IR thermometer I like to use on trips on the wheel hubs and the differential.

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Arkansas_V8

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This is true but then again I have never read of a damaged Diff case from dragging it over everything. I jthink I would just prefer to add lockers to both axles and more power

And you will still end up hung up.

Do you consider moving from a 36" tire to a 40" tire a big gain in clearance? 2" gained under your axle is the same as a 4" tire size increase.
 

Blue Ox

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If you actually watch the videos he uses instrumentation and transparent covers that replicate the shape of aftermarket covers. As frankenchevy said they interfere with the trajectory of the oil to the pinion and some that allow extra fluid, cause it to aerate severely at highway speeds.

Rears are pretty tough, as their survival attests. But the claims of the aftermarket appear to be based on pure speculation and no actual testing or engineering.

I'm rarely impressed with Mr Banks, but this time I thought he did a good job of testing and analysis.
 

Arkansas_V8

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I drive my truck from and to the trails. And most of the time I just cruise at around 60- truck seems to like it and I've never had any issues.

But several years ago a trail took me longer than I thought and I had to haul butt back home to pick up my kid from school. So I did an hour of highway driving at 70-75 mph. Screaming along at 3500 RPM made it in time. But when I got out of my truck I smelled oil- my 14 bolt rear diff puked its fluid out of the vent hose attached onto the underside of the bed. Differential was very hot. It has never done this again- but I haven't driven that fast. In fact I drove it to my parents a few weeks ago with a load of firewood on the highway. It's 2.5 hours by highway (at 60 mph) to get there.

Why? Was it the aftermarket thick cover?

You must be registered for see images attach


Was it the fact that my exhaust dumps before the axle and maybe all that exhaust was heating it up?

Don't know.


I am gonna go diff cover, not the exhaust pointed at it(ask Banks). Makes the most sense.

My vapor lock was because it's hot outside, and I dont have an OEM fuel filter. Nothing to do with my tucked exhaust being like 4" away.
 
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Arkansas_V8

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If you actually watch the videos he uses instrumentation and transparent covers that replicate the shape of aftermarket covers. As frankenchevy said they interfere with the trajectory of the oil to the pinion and some that allow extra fluid, cause it to aerate severely at highway speeds.

Rears are pretty tough, as their survival attests. But the claims of the aftermarket appear to be based on pure speculation and no actual testing or engineering.

I'm rarely impressed with Mr Banks, but this time I thought he did a good job of testing and analysis.

He did fantastic.

Now time to tell everyone to go back to stock. Swap before you hit the rocks.
 

colonel mustard

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This is true but then again I have never read of a damaged Diff case from dragging it over everything. I jthink I would just prefer to add lockers to both axles and more power

I have lockers...the center of the diff sometimes catches an obstacle. so I shaved
 

colonel mustard

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I can find no corroborating evidence to the cracked ring gear theory.

Notice all 14 bolt covers look darn near stock, even after market.

I am thieving other peoples engineering.

I will carry on, and be the first to tell you all if I crack a ring gear dailying/bashing a shaved 14 bolt, or have any other issues.

I may have misspoke....it was a concern I found when researching which direction I wanted I wanted to go. and the main concern wasn't the gear cracking....it was the decreased amount of fluid was thought to be a concern in effecting cooling while on long trips or more specifically towing.

as far as engineering is concerned....to all the people that are using GM's million dollar R&D on the 14 bolt as being there reason not to shave. I don't buy that. that's like saying there factory suspension was designed perfectly for the truck from the factory so you should only replace it with factory parts. fact is ….the 14 bolt was designed for towing and heavy loads...not offroading. which is why there is room for improvement if you plan on using your truck for offroad.

everyone has there own beliefs I suppose....but this isn't a "new" thing. its been R&D'ed but a ton of offroaders

anyways....cheers.

if you have a shaved 14 bolt I would love to see pics of your work.
 

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I may have misspoke....it was a concern I found when researching which direction I wanted I wanted to go. and the main concern wasn't the gear cracking....it was the decreased amount of fluid was thought to be a concern in effecting cooling while on long trips or more specifically towing.

as far as engineering is concerned....to all the people that are using GM's million dollar R&D on the 14 bolt as being there reason not to shave. I don't buy that. that's like saying there factory suspension was designed perfectly for the truck from the factory so you should only replace it with factory parts. fact is ….the 14 bolt was designed for towing and heavy loads...not offroading. which is why there is room for improvement if you plan on using your truck for offroad.

everyone has there own beliefs I suppose....but this isn't a "new" thing. its been R&D'ed but a ton of offroaders

anyways....cheers.

if you have a shaved 14 bolt I would love to see pics of your work.

Okay, cause I kept searching. Lol

If you look closely at a shave, you lose like two maybe three syringes worth of fluid.

Not even a big syringe, the kind I give my youngest his medicine in.

Your work looks good, let me know when it starts puking fluid because you dont have a stock cover anymore.
 

Blue Ox

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Oy! I'm really sorry I got involved.

Nobody ever said not to shave one for offroading. I was only pointing out that since there were some concerns about the gears that it may have more to do with people putting aftermarket covers on them than shaving the gear.

I never imagined everybody would get so butthurt about shaving their rear. :rolleyes:
 

Arkansas_V8

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Oy! I'm really sorry I got involved.

Nobody ever said not to shave one for offroading. I was only pointing out that since there were some concerns about the gears that it may have more to do with people putting aftermarket covers on them than shaving the gear.

I never imagined everybody would get so butthurt about shaving their rear. :rolleyes:

I am not butt hurt.

But imagine a guy that doesn't know any better comes across this thread.

I have some good knowledge, and more research than I should on this subject.

I just had to counter Gale Banks, and any nay sayers. Let them know they will be safe.

I have never heard of a lack of fluid from a shave causing any issues, or a "tuff" diff cover causing issues.

I have to know these things, I have to study it if even one person mentions an issue.

This is my daily, and I study every single thing I do to it.

I urge you to watch any year of Ultimate Adventure.
 
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Arkansas_V8

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I look at that like I should only ride dual sports, because towing my motocross bike is lame. Which is silly.

The really purpose built stuff isn’t always street legal.

I think it’s all cool if people are having fun with stuff they’ve earned. I respect it all.

I said in quotes purpose built.

My statement ment more like if I trailered my Suburban to the trails, or you trailered your dual sport to the trail.
 

colonel mustard

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Okay, cause I kept searching. Lol

If you look closely at a shave, you lose like two maybe three syringes worth of fluid.

Not even a big syringe, the kind I give my youngest his medicine in.

Your work looks good, let me know when it starts puking fluid because you dont have a stock cover anymore.


lmao...yeah ill you know...if you do the same lol.

is it really only that small of an amount?? man everybody made it seem like it was a quart..maybe one day I will do the full shave....I mean the full shave does look good as ****
 

Arkansas_V8

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lmao...yeah ill you know...if you do the same lol.

is it really only that small of an amount?? man everybody made it seem like it was a quart..maybe one day I will do the full shave....I mean the full shave does look good as ****

I have had one friend do a full shave, you are barely cutting into diff housing.

I will update you.
 

QBuff02

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All you guys over here arguing about shaving differentials for clearance and if its still strong or not, and to keep it from dragging and I'm sitting over here thinking about the old 4x4 club from these parts back in the day. 42" swampers or gumbo monster mudders were about the average for most guys and in that thick river bottom gumbo I saw many a truck plowing with their pumpkins and axles completely buried under the mud. Horsepower seemed to be the key back then, and i'm thinking it still is today. The bumpers on those truck were waist to stomach high on me at the time and that little extra bit of ground clearance wasn't gonna make any difference when said bumpers were down at ground level in some of the mud holes they played and got buried in. But it was also the nature of our beast. If rocks and stuff are your thing, I can certainly see how one would benefit from that modification. I don't think cutting/shaving a little off the diff is going to make (or break) anything. But I can guarantee one thing, and that is horsepower WILL find the weakest link!
:driver:
 

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