ATF: Bighorn - Owners Manual Error? Safety issue?

[MTPockets]

My Heartland Owners Manual says the Pin Box Mounting bolts should be torque'd to 70 ft. lbs. and checked per instructions. I'm a stickler on all by bolt torques and do check frequently and find loose nuts. The pin box bolts have had some loose every time I checked and it was a bit concerting. I re-checked that torque spec on the Mor Ryde web site and find the spec calls for 135 ft. lbs torque for 5/8" grade 5 bolts, which I have. 135 makes more sense .... Heartland may say the manual spec is for a standard pin box, but the manual doesn't say that, and, there was no information about MorRyde with my stuff ... I've been pulling this 5th wheel around with loose bolts, torque'd per my manual, but in a potentially hazardous situation .....

Why does my manual call for 70 ft. lbs.? Why did I not get the proper information in my paperwork folder for the MorRyde specs? I depend on these manuals to be correct and it shouldn't be my responsibility to double check the information, although I did happily stumble on this one. Now, 'is' the 135 correct?

 

[karykatz]

MTpockets,

The standard lippert pin box mounting specs require 95-110 ft/lb torque for mounting bolts. the optional morryde hitch require 135 ft/lb torque for mounting the bolts.

I hope this helps.

 

[jbeletti]

Terry,

I know you now have the Mor/ryde Rubber Pinbox Installation Manual that contains the torque value table.

Just wanted you to know that for everyone else, I have placed a copy of this on HOM (Heartland Owners Manuals) and it can be accessed from this link.

Thanks for pointing this out and Heartland will work towards language modification in the owners manual.

Jim

 

[JohnDar]

To be sure, the 5th AB instructions recommend 150 ft-lbs. for 5/8" Grade 5 bolts. The torque requirement is also dependent on the finish used on the bolts. A plain finish is rated for 150, galvanized is 188, and waxed is only 75. Here's a handy torque chart from a bolt manufacturer.