Pin Box Bolts torque

Bolt torque chart:

Chart


And on the same site:

Bolt material identification

Mine torque to 75 ft. lbs. YMMV. Best to check the manual.

Measure the bolts. Mine were 5/8 Grade 8 bolts, 150 ft. lbs.

Rich

75# sounds awful low for hitch bolts supporting a "X" lb 5er.

My Lippert frame manual on our 2014 Bighorn recommends that the pin box bolts be torqued to 110 foot pounds.

After taking delivery from the factory on an ordered new unit I checked the pin box bolts. Out of ten bolts, eight were less than 110# torque. Five of those eight were lower than 75# torque.

I hauled the RV from Maine to Florida then on to Arizona, about 3700 miles, where I rechecked the torque. Eight of the ten bolts were at specs and the other two bolts were within five pounds of factory specs (110#).

I rechecked the torque after arriving back to Maine (4500 miles) and found all bolts were at 110#.

Lakeside

I would verify what grade the bolts are and if not eight I would be investing a couple or so of bucks into grade eight.

Terribly unprofessional i now but I used and arm strong torque wrench on mine. :W Then I hand brushed black paint on the ends and have always checked for cracks in the paint. Haven't moved since i replaced them with grade 8 a few years back.

lakeside013104 wrote:
My Lippert frame manual on our 2014 Bighorn recommends that the pin box bolts be torqued to 110 foot pounds.

After taking delivery from the factory on an ordered new unit I checked the pin box bolts. Out of ten bolts, eight were less than 110# torque. Five of those eight were lower than 75# torque.

I hauled the RV from Maine to Florida then on to Arizona, about 3700 miles, where I rechecked the torque. Eight of the ten bolts were at specs and the other two bolts were within five pounds of factory specs (110#).

I rechecked the torque after arriving back to Maine (4500 miles) and found all bolts were at 110#.

Lakeside

X3 to 75# being too loose! I moved mine up and tightened to 110#, the biggest issue is getting them loose! I found that my air impact wrench fit into the pin box so I get to the nuts.

"X3 to 75# being too loose! I moved mine up and tightened to 110#, the biggest issue is getting them loose! I found that my air impact wrench fit into the pin box so I get to the nuts."
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Hold on, look at that bolt torque chart I referenced above. 75# is right for 1/2 inch grade 8 coarse thread bolts (The chart shows 80# max). Over torquing leads to stretching the bolts which weakens them. If the bolts are 9/16" diameter then 110 is good(115 max for grade 8). So first determine what size bolts are installed then figure out what to torque them to. The manufacturers seem to specify a torque that is 5# less than the max.

Seems I misspoke about my pinbox bolt torque. They do torque to 110 ft. lbs. That is why I have the manual in my 5er and not my head.