Fuel Tank Skid Plate Torque

I'm looking to replace the plastic OEM fuel tank skid plate with an RCI steel skid plate. What is the torque spec on the nuts for securing the tanks strap studs to the plate. RCI said it should be 28 FT-LBS, but wanted to verify. 2024 Tundra Platinum w/Off Road Package

 

US bolts with tension approximately 70% of yield strength. The values are for slightly lubricated bolts. For dry bolts increase the torques with approximately 30%.


Aproximation formula:

The relation between applied torque and axial force - or load - in a bolt can be calculated in this general equation as

T = K F d (1 - l/100) (1)

where

T = wrench torque (Nm, lbf ft)

K = constant that depends on the bolt material and size

d = nominal bolt diameter (m, ft)

F = axial bolt force (N, lbf)

l = lubrication factor (%)

Typical values for K with mild-steel bolts in range 1/4" to 1":

• normal dry: K = 0.2
• nonplated black finish: K = 0.3
• zinc-plated: K = 0.2
• slightly lubricated: K = 0.18
• cadmium-plated: K = 0.16

So verify your bolt grade and diameter. More than likely RCI is providing the correct torque. Welcome to the forums.

 

and all the bolts on a tundra are metric.....

 

Most American vendors making aftermarket parts use US bolts but I agree some of the bolts that directly attach to the frame rails will be metric the pdf has all the info to calculate torques on metric bolts.

 

The bolt its probably a m10 or m12 so torque it to 42 ft-lb's or 73 ft-lb but that table is for 85% of proof load in the table, so we have to divide by 0.85 to get to yield and then multiply by 0.7 to get to the dry bolt recommend torque.... Literally was using these equations checking a tensioning profile for a wind load acting on a geomembrane liner the other day, but would never choose to answer a "What torque should I tighten the bolts on my truck to"....most people aren't engineers or engineer minded so maybe equations aren't that helpful?? IDK but hey its an answer I guess. Bottom line is follow the Toyota manufacturer recommendations is correct answer here. 28ft-lb is probably the right answer here. I mean the torque for Toyota lugnuts for aluminum wheels is 97 ft-lb...I mean the torque to get to the lug's yield is higher but that doesn't' mean I'm going to torque it to that....I'm going to go off what the Toyota engineers recommend it should be torqued to. Then there is the whole accuracy of torque as a measure of tightness not really being accurate but we won't jump down that rabbit hole.

 

also......

 

There’s no bolt per-se, it’s a stud that’s installed on the tank “strap”, I’m torquing the nut and it’s an M8 Nyloc nut.

 

Follow what RCI says and you'll be good.

 

This is impressive, I feel smarter now

 

Fastener torque is very interesting and difficult topic and varies widely in different fields these are just approximations. Some can spend their entire life like some of our ancestors did researching and debating this topic. I won't lol I just like bolts or anything with threads it's the core of my job and I find it simple yet not so simple.

We should all feel smarter everday we wake up or we're doing something wrong lol.