trailer ball capacity / shank size

[FTG-05]

I bought a torque wrench that I keep in my tow vehicle just to make sure the ball is secure.

Some of my hitches have no-rotate balls and have yet to find one loose... also, a fresh lock-washer does a fine job when used.

I have an eclectic assortment of trailers and tow with the following size balls:

1" (Single Wheel Camp trailer from 1957 that uses two 1" balls)

1 3/4" (Around the yard)

1 7/8"

2"

2 5/16"

2 1/2" inch on a custom trailer built in the 1930's... hitch, ball, trailer were all custom made.

Actually, according to one NASA test conducted years ago on fastener thread locking mechanisms and processes, the so-called lock-washer came out as worse than useless. In other words, it performed worse than with no thread locking mechanisms or processes at all.

I know on the International Space Station, NASA forbade the use of lock washers; and, presumably, on all space flight hardware. A lot of those reasons had to do with requirements in addition to thread locking ability, however (i.e. off-gassing, FOD reduction, captive fastener requirements, etc.)

Unfortunately, I cannot find that test report (probably on my work PC and I'm retired now), but here's probably the next best thing: Pirate4x4.Com - Extreme Four Wheel Drive Specifically, read the bottom of page 12 in the .pdf.

I haven't used spring lock washers since at least the early '90's and I never will.

Good luck!

 

[klm]

Just out of curiosity does anyone know of a case where the ball or shank failed?

 

[bcp]

A couple of lock washer reports, including NASA:

http://www.tractorbynet.com/forums/build-yourself/180148-lock-washers-dont-work.html

Bruce

 

[tcartwri]

Actually got the Harbor Freight 3/4 socket set for this and put the stinger in the receiver on its side and step on the wrench handle until tight, think one of the balls had a spec of 480ft lbs so 2 foot handle and 240lbs will do it.

David Kb7uns

Yup. We have a torque wrench at work that will do 600 ft.lbs and it's three feet long and I recall it was close to $700 a decade ago.

The lock washer is just there to keep the nut from completely falling off imo. It's the stretch of the shank that keeps the assembly together.

 

[tcartwri]

Excuse me... it was $1900 :confused2:

 

[ultrarunner]

The set of balls I bought when I bought my truck in 1985 all had split lock washers... the 2000# 1 7/8, the 3500# 2" and the 10,000 # 2 5/16

I've noticed a 1" washer will physically tear metal off the mating surfaces the first time taken apart.

Could be I'm working with old data?

My antique cars all have Castle Nut with cotter pins everywhere... about the only place a modern car may have this is at the wheel bearings.

Also a big fan of the various thread lockers... although I have never used one on a trailer ball.

I did have a trailer come loose once and it was my fault for letting someone else hitch it up to the truck.

Back then, I used Convert a Balls because no tools needed to change ball sizes... the 1 7/8 ball got a lot of use from the box trailer and the locking pin that holds the ball to the shank was no where to be found when the trailer with ball came off the back of the truck.

My best guess is when my helper changed the balls the pin slipped out and not knowing it was missing, set the ball on the shank...

Lucky nothing was damage... again, very lucky!

Ever since then I personally check the mount before driving off... heard to many stories where people have hitched up and come back to find something amiss.

A friend had similar and the reason is someone had tried to steel his trailer... the coupler was open and the one of two safety chains without a lock was dragging... without the lock he could of lost the trailer two ways... theft or going down the road.

 

[schmism]

I slide the hitch in sideways into the mount then put my 3/4" drive HF socket on it and a 4' cheeter bar and use my weight to tighten the balls.

before I had my 3/4" drive HF set i used a pipe wrench and cheeter bar.

 

[Capt Dan]

"Just out of curiosity does anyone know of a case where the ball or shank failed?"

I've only heard of the balls loosing the nut and lifting off the hitch. It happened to a friend of mine when he hit a bump at a bridge. With a heavy 26 foot trailer.