Differential Cover Bolts

[Silverback]

WARNING!
It is next to impossible to get any sort of tech support from DANA. I went thru half a dozen menus, then several menu options, only to have the tech tell me that he couldn't find the rear end specs. When I asked about the bolts he flatly said, "We don't recommend changing any of the bolts."
Sounded like my dad.

The serrations on the flange are uni-directional (preventing loosening). That should not affect the ability to properly torque the bolts.

Honest, not trying to rain on your parade here, but the serrations will affect the torque value as you tighten them. Would I use them? No, but then I'm anal as hell about those things. Will you have any problems with them? I would be willing to bet that you won't.

Be sure to take some pictures when you are done. We love pictures.

 

[Begood]

Especially pics of Naked women.

Bill.

 

[Kevan]

Silverback- I'm not worried about a little rain. Unless it's going to rust out the bolts again. LOL

I would appreciate it if you could explain to me why/how the uni-directional serrations will affect torque value.

Something I noticed while looking at the previous pics I took:
- The bolt that holds the linear shock in place is galvanized, probably Grade 5 or under. It's also a little too long for my taste.
- The bolt that holds the shock mount to the diff. cover is also Grade 5 or lower.

I think there's more to worry about regarding the linear shock mount than the diff. cover itself.

 

[Silverback]

Silverback- I'm not worried about a little rain. Unless it's going to rust out the bolts again. LOL

I would appreciate it if you could explain to me why/how the uni-directional serrations will affect torque value.

Something I noticed while looking at the previous pics I took:
- The bolt that holds the linear shock in place is galvanized, probably Grade 5 or under. It's also a little too long for my taste.
- The bolt that holds the shock mount to the diff. cover is also Grade 5 or lower.

I think there's more to worry about regarding the linear shock mount than the diff. cover itself.

Uni-directional serrations will still cause drag on the adjoining surface as the fastener is being tightened. They will actually cause some displacement of metal on the cover as the cover is softer material than the fastener. Does that make sense? If not let me know and I will take another attempt at explaining that part.

Okay, now to part 2 of your question. The two bolts that are holding the shock (one at each end) are being subject to shear loads. In the case of these bolts they are in a double shear condition. For these bolts to shear they would have to shear in two places, not one since they are in essense in a clevis. Also bolts have much greater strength in shear than they do in tensile loads.

Hope that helps.

Almost forgot. Grade 5 bolts will have 3 hash marks on the head. Grade 8 have 5 hash marks. Leave it to those damn engineers to make if confusing.

 

[Kevan]

Silverback- I hear ya.
What's the difference between a split lock-washer and serrations? Aren't they both going to mark the cover?
How much will the serrations affect the torque amount? 1 ft-lb.? 5 ft-lbs.?

Here are some shots of the original bolt and the new S/S one:

http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010005.JPG
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010009.JPG
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010011.JPG
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010023.JPG

Also, in regards to the shock:
I was referring to the small single bolt that holds the shock mount to the actual diff. cover plate.

I will check for markings on them next time I'm under the truck.

 

[Silverback]

Silverback- I hear ya.
What's the difference between a split lock-washer and serrations? Aren't they both going to mark the cover?
How much will the serrations affect the torque amount? 1 ft-lb.? 5 ft-lbs.?

Here are some shots of the original bolt and the new S/S one:

http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010005.JPG
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010009.JPG
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010011.JPG
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010023.JPG

Also, in regards to the shock:
I was referring to the small single bolt that holds the shock mount to the actual diff. cover plate.

I will check for markings on them next time I'm under the truck.

Yep, both will leave a mark. Lock washers acheive there intended function by one large gripping point verse many small one on a serrated flange fastener.

I cannot answer the required torque question off the top of my head. Let me check some books at work tomorrow. I will add that to my knowledge I do not remember any situation where serrated fantener are used when torque is required. Doesn't mean it doesn't happen, just that I have never see one.

Looking at the pictures you posted it appears that the factory uses Locktite to retain the fasteners. If/when I replace mine, that is what I will use.

On the shock mount, I will have to crawl under the truck sometime this weekend if I get time to see exactly what you are referring to. The one thing I can almost gauratee is that the factor of safety on that fastener will be at least 1.5 to 1. My guess it will actually be 2.0 to 1 or higher.

 

[Kevan]

I cannot answer the required torque question off the top of my head. Let me check some books at work tomorrow. I will add that to my knowledge I do not remember any situation where serrated fantener are used when torque is required. Doesn't mean it doesn't happen, just that I have never see one.

Thanks. I'd appreciate that info.

Looking at the pictures you posted it appears that the factory uses Locktite to retain the fasteners. If/when I replace mine, that is what I will use.

That's not Loctite. It's plain blue RTV/gasket sealant.
There was no thread locker on any of the bolts I removed, nor did I apply any to the new S/S ones.

On the shock mount, I will have to crawl under the truck sometime this weekend if I get time to see exactly what you are referring to. The one thing I can almost gauratee is that the factor of safety on that fastener will be at least 1.5 to 1. My guess it will actually be 2.0 to 1 or higher.

The bolt that holds the shock to the mount isn't rated. It has a non-standard shape to the head.
The bolt that holds the bracket to the diff. cover is rated, but I couldn't read it unless I pulled the shock off (not happening tonight).

The S/S bolts are in. They look great. Factory recommended torque is 35 ft.lbs. I set the wrench to 36 ft.lbs.

BEFORE:
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010180.JPG
AFTER:
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010029.JPG
TOOLS:
http://www.tremol-no.com/images/woodblock/srt10reardiff/P1010026.JPG
(1) Tube of blue RTV/gasket sealant
(1) 9/16" socket
(1) 3/8" socket driver
(1) 3" extension
(1) 6" extension
(1) Torque wrench
(1) light (I did most of the work at night, plus....it gets kinda dark under there, even in the daytime.

A quick test drive around the block, and everything is working great.
I will check for leaks tomorrow.

 

[Silverback]

You will not find torque ratings for serrated flang fasteners unless they are through bolts and then you would have to torque them from the nut side.

As I stated, I would not sweat it. I'm sure you will be fine.

It looks nice in the picture. Good job. :rock:

When I opened the Tools picture I was expecting to find a bunch of empty beer bottles, or a bunch of banana skins.

 

[Kevan]

Thanks for the help, Silverback. I appreciate it.

Next is to Penetrol all the metal parts underneath (as Kalani suggested). Hopefully he'll post some pics this weekend. I'm curious as to what it looks like, and how difficult it is to apply.

Maybe someday I'll get a wild hair and get a bucket of regular carbon steel bolts and have them powder-coated Viper red. Then offer sets at cost to the VTCOA members.

I save the beer (and bananas) for AFTER the work is done.

 

[kalani]

Here you go.

Keep in mind that the flash on the camera makes it look a bit un-natural.

The more time you spend cleaning the rust first - the better the result. I got a little lazy on some of mine so they still have a slightly rusty tint.

You can see the tag on the rear diff is its original metal colour but some of the bolts are still alittle redish.

 

[mauiSRT/10]

Thats more knowledge about bolts than I would have ever guessed I could learn in one day! I'm tired......I think I need a cold beer! LOL

patrick

 

[Django]

Hey, is anyone making a chrome cover for the differential?

SD

 

[mauiSRT/10]

How about a Viper SRT/10 one? Wait a minute....my mod wishlist is already overflowing!

patrick

 

[Kevan]

Finding ANYTHING for the Dana60-HD rear end is a huge PITA. Even the guys at Dana asked, "We make an HD version?". *sigh*
Don't hold your breath waiting for aftermarket stuff. You might check a dually forum. They may have found some stuff.

Kalani- the pics look GREAT!!!
Could you give a quick description of the process with the Penetrol? Prep work on the under-carriage, application process (spray? brush? sling from fingertips?), etc.

Thanks!

 

[kalani]

Finding ANYTHING for the Dana60-HD rear end is a huge PITA. Even the guys at Dana asked, "We make an HD version?". *sigh*
Don't hold your breath waiting for aftermarket stuff. You might check a dually forum. They may have found some stuff.

Kalani- the pics look GREAT!!!
Could you give a quick description of the process with the Penetrol? Prep work on the under-carriage, application process (spray? brush? sling from fingertips?), etc.

Thanks!

Kevan - buy it in a aerosol can and just spray it on like wd-40. Before spraying make sure you give the bad sections a going over with some rust converter, then wipe it off - this will get rid of all the rust so when you coat it in penetrol it will stay this way.

Penetrol is basically a clear oil based film that dries to a flexible, clear film. It seals the metal so it wont rust, but if you spray it over rust - the rust will stay there (it wont get worse) but you will see it. Thats why i used some septone underbody deadner to cover it afterwards.

http://www.septone.com.au/detail.asp?item_cat=5&item_number=205&page_num=2

 

[Kevan]

Thanks Kalani.

I'll be picking up the rust converter and Penetrol tomorrow. With any luck, they'll have both in aerosol cans...at the same store.

 

[kalani]

Thanks Kalani.

I'll be picking up the rust converter and Penetrol tomorrow. With any luck, they'll have both in aerosol cans...at the same store.

You need to apply the rust converter with a brush and gloves - its like honey, make sure you let it work then rub it off and let it dry.

It will work wonders!!

 

[TheSickness]

You need to apply the rust converter with a brush and gloves - its like honey, make sure you let it work then rub it off and let it dry.

It will work wonders!!

I bet Vegimite will do the same thing Sam :call:

 

[Kevan]

I've seen both the gallon cans and aerosols for the rust converter stuff.

Gloves? Count on it.

 

[Silverback]

Hey, is anyone making a chrome cover for the differential?

SD

I'm guess that at least for the RC's we are stuck with what we have. I do not believe any of the other trucks have the torque shock on the top and that mounting is part of the cover casting.