Pinion nut torque setting

[Bill W]

While waiting on more brake parts for my deuce I decided to change the pinion seal(s), can anyone tell me what the torque setting is for the pinion nut on the drive flange, or which TM to find it in as I already did a search and went through the TM 209-20s.
Thanks in advance

 

[319]

Bill did you look at TM 9-2320-361-24-1? Should be in there, although I have not looked.

 

[rosco]

I don't know the technical answer, but usually, it is as much as you can get. Its often hard to torque them.

Lee in Alaska

 

[rosco]

Torque settings there are deceiving! Because if you can get a torque wrench on it (keeping it from turning, while your at it), you will want to make it to the next notch in the nut, so you can get the cotter pin in to lock it. Use an impact on it, and call it good, and it will be.

Lee in Alaska

 

[Bill W]

Lee
Just a FYI

I've been told by many of a truck mechanic to never use a impact on anything connected to bearings as you could damage the cups/races from the hammer/chatter effect of the impacts, and torquing the pinion nut sets the preload for the pinion bearings.
I did put a cheater bar on my breaker and was able to put the nut back to where the cotter went back in the same hole but I,m gonna check the TM 319 mentioned just to see what the actual #'s are, My M-37 was somewhere around 300ft/lbs so I'm pretty sure these will be at least that or greater which is more then my 250lb T/wrench so I guess it'll be a setting of 1.5 on the nut buster scale and leave it at that

 

[gringeltaube]

I've been told by many of a truck mechanic to never use a impact on anything connected to bearings as you will damage the cups/races, and torquing the pinion nut sets the preload for the pinion bearings.
.......................

Yes, this applies to diffs which have a collapsible spacer for the pinion...

In our case .....
impact or not, tighten "all you can" and just that little more, to fit cotter pin. Never back up to align holes!

G.

 

[dittle]

Lee
so I guess it'll be a setting of 1.5 on the nut buster scale and leave it at that

Dang that is an awesome quote, will have to use it myself when I'm changing out the tracks on the M60 in a month or so

 

[rosco]

Yes, I know about the bearings & the Preload. All that is well and good, but on the real big stuff, there is the practical matter of using a six foot cheater bar under a truck so that you can maintain, no more the "1.5" on Bill's scale.

As a practical matter, you would have to have the truck backed against a tree, and somebody on the brakes, to torque the specified preload. If the truck rocks, your bar/wrench, will be too long. 3 & 4 hundred foot pounds of torque is hard to do, any time, and especially hard to do, on something that wants to turn anyway. Then you want to go to the next notch in the nut - that blows the "Spec" anyway. You have book "Specs", then you have how things are done.

Lee in Alaska

 

[JasonS]

Anybody ever take out a shim or two to tighten up the preload? I have a little lateral movement once it is warmed up.

 

[rosco]

Pinions need adjustment from time to time. If there is side/end play, your seal won't hold. Take out a shim or two, to zero out the play. The shims set the "preload "(which isn't much), on the bearings. The pinion nut on the end, holds the assembly together.

Lee in Alaska

 

[OPCOM]

The M35 pinion nut torque spec is 300-600 LB-FT. The nut is 1.5" size. Don't ask me how to do it easily, the truck wants to move and the torque wrench is rather long in the space between rears.