New U-Bolt Questions

[Kevan]

Hey folks.
I just dropped about $100 on new Grade-5 U-bolts for the truck.
They're replacing the non-correct-length ones that came with a (will-remain-unnamed site vendors) lowering kit and malformed badly when I torqued them down.

BOLT SIZE: 5/8" dia. x 3-5/8 radius x 9-1/2" length; fine thread.

Two questions:
- Should I return the Grade-5 bolts and get Grade-8?

-The lowering kits bolts corroded within a week. They are now bright orange (pics available upon request).
I would like to prevent said corrosion on the new bolts.

What's the best way to protect them?

Note: the bolts are now chrome-ish in color. I would prefer a black bolt to match the rest of the components under the truck, but....if the suggested protection works, I don't care what color it is.

Thanks for the help.

 

[dave6666]

Black oxide or phosphate. Not DIY if done right.

 

[Kevan]

Dave- is that protection or color or both?

 

[dave6666]

Dave- is that protection or color or both?

Both. Google 'em for more than you can stand on the technical description front.

Most industrial plating shops can do it. Not a "chromer" shop thing...

 

[Kevan]

Thanks Dave.
Did a bunch of reading on black oxide coating. It's sort of like a black anodizing for steel.
Local (Cleveland) quote for (4) U-bolts was $67.
The other downside is that even with black oxidizing, the part can still rust. *sigh*

A couple of things I noticed this morning:
- OEM bolts have NO markings, so I'm not sure what Grade (if any) they are.
- OEM bolts have coarse thread; new Grade-5 bolts have fine thread.
- OEM bolts are 9/16" dia.; new Grade-5 bolts are 5/8" dia.

 

[dave6666]

How about some Duplicolor VHT in black, over the black oxide? A local biker shop recommended that paint for under chassis parts as it has ceramic in it making it more durable than regular paint. I did my sill vents in it - just bare aluminum underneath - and with all the sand bits I find everywhere down there they are still perfect.

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[Kevan]

IIRC, aluminum dissolves when BO coated, no?

I'm not a fan of paint for these parts because of the 'stretching' that the bolts do when fully torqued. The paint will crack/chip really easily.

However, I've become a big fan of "truck bed liner" paint for protecting parts. I used it on the custom fuse holder mount plate in the engine bay, and it's worked out great.
The other advantage is that it's sort of flexible when dry, so it'd be able to 'give' slightly when the bolts get torqued.

Thankfully, this isn't a major project or a difficult-to-access part (though my garage floor is colder than Hillary Clinton's heart).
I may try a few methods (paint, BO + oil dip, powder coating) and see which wins the battle.

Thanks for the tips!

 

[Kevan]

Well, the new U-bolts did not get installed.
5/8" is too large of a diameter to fit through the lower spring pack plate.
Looks like I need to find 9/16" x 3-5/8" x 9-1/2". *sigh*

Here are a couple of pics that are NOT FOR THE SQUEAMISH!!!

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[bluesrt]

looks like after u get those better u clamps,make shure the bolts are straight up to the lower mount brackets,will help not to disfigure the clamps.looks like the top u part is to close(inward towards the springs)

 

[Kevan]

The bolts are perfectly level/parallel with the spring pack.
What you're seeing is about 10% perspective of the shot, and about 90% malformation of the cheapass U-bolts after they were torqued to spec (110 ft.lbs.)

What concerns me more is the virus of corrosion happening with each passing day/mile.
Getting rid of all that will be quite the treat.