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So I get home today and during my post-trip...with a combination of wet weather and sheer luck...I was FINALLY able to locate the ever-so-slow air leak in my front left drive tires. So, I figure I'll pull the tire off the truck and take it to town with me when I am out running errands tomorrow morning. I thought about rolling the inner wheel up onto a 2x4 (leak was on the outer wheel...the only advantage I've found to having budd wheels) but decided to use my jack instead. While under the truck positioning the jack, I found that both U-bolts on that side of that axle were a little loose. :blink:

Had the leak not been audible...and had I not made the decision to do extra work and jack up the tire instead of doing it quick & easy with a 2x4...who knows when/where/how those loose U-bolts would have made themselves known! :o

On the plus side, I get to buy another 3/4" drive deep well impact socket. 1-1/4" was too small....1-1/2" was too big....don't have anything in between...yet. Even tried using my non-impact 1/2" drive sockets to size the bolt figuring maybe it was metric...but all I had was 32mm (too small) and 36 mm (too big). :pat:

When approaching a 4-way stop, the vehicle with the biggest tires has the right of way!
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AND while your wandering the tool section, you can pick-up another "toy".

Tools, never have enough. Also business expense!

Success is only a stones throw away.................................................................for a Palestinian

and i've heard somewhere along the line that you should use a torque wrench or breaker bar to tighten u-bolts because an impact wrench won't tighten them properly?..I don't know, but i've heard that somewhere.

Producer of poorly photo-chopped pictures since 1999.

and i've heard somewhere along the line that you should use a torque wrench or breaker bar to tighten u-bolts because an impact wrench won't tighten them properly?..I don't know, but i've heard that somewhere.

I asked a mechanic at the Mack dealer what the torque specs are for the u-bolts and he said "I don't know. I usually just use a 3/4" impact and run it as tight as it'll go"

Not sure if that's right or not, but with my gun that'll put 'em somewhere between 900-1100 ft lbs.

When approaching a 4-way stop, the vehicle with the biggest tires has the right of way!

I think Rowdy has the Mack air ride, which is made by Hendrickson and is identical to this:

http://www.hendrickson-intl.com/products/product_detail/has_tandem.asp

Those U bolts are tiny compared to the ones on any of the Mack camelbacks.

If the U bolts have been on there a while, tightening may be impossible, and the U bolts may need to be torched off and replaced, then tightened properly, and retightened after running it for a day.

I also use a 3/4 impact @175 PSI air pressure and tighten as tight as it'll go, whack the tops of the U bolts with a sledge a few times, then tighten some more till they don't tighten any further.

.

"If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

I think Rowdy has the Mack air ride, which is made by Hendrickson and is identical to this:

http://www.hendrickson-intl.com/products/product_detail/has_tandem.asp

Those U bolts are tiny compared to the ones on any of the Mack camelbacks.

If the U bolts have been on there a while, tightening may be impossible, and the U bolts may need to be torched off and replaced, then tightened properly, and retightened after running it for a day.

I also use a 3/4 impact @175 PSI air pressure and tighten as tight as it'll go, whack the tops of the U bolts with a sledge a few times, then tighten some more till they don't tighten any further.

.

Yup. That's what I got. Was going to buy 2 new u-bolts and all the necessary hardware for 'em, but Mack only had 1. Hopefully I'll be able to re-use at least 1 of 'em. Also bought a 3/4" drive 1-5/16" deep well impact socket which fits the nuts, as well as a 1-5/16" combination wrench for the side box. Got the tire patched. Now I have all day tomorrow to git'er done.

When approaching a 4-way stop, the vehicle with the biggest tires has the right of way!

I worked in the SLC, Utah Mack Dealership in the late '70's.

Some of the bolts were 1900 foot pounds of torque.

The shop foreman would pick the right number of guys and we would hang off of a cheater pipe.

"Yep, that's 1900 fp - - - go back to work"

I'm still laughtin'!!!!!

Packer

Keep a clutchin'

A 10 foot cheater pipe with a 190 lb. guy hanging on the very end of it would give 1900 ft. lbs.

That would work very well for torquing things in a vertical plane such as wheel lugs or bolts in the side of a frame, but wouldn't work for fasteners which are in a horizontal plane, such as spring U bolts.

.

"If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

A 10 foot cheater pipe with a 190 lb. guy hanging on the very end of it would give 1900 ft. lbs.

That would work very well for torquing things in a vertical plane such as wheel lugs or bolts in the side of a frame, but wouldn't work for fasteners which are in a horizontal plane, such as spring U bolts.

.

Just lay the truck over on it's side and the horizontal plane becomes a vertical one :thumb:

When approaching a 4-way stop, the vehicle with the biggest tires has the right of way!

and i've heard somewhere along the line that you should use a torque wrench or breaker bar to tighten u-bolts because an impact wrench won't tighten them properly?..I don't know, but i've heard that somewhere.

Tom,......I know where you heard that..............................from somewhere in Farmington, IL.

mike

I think Rowdy has the Mack air ride, which is made by Hendrickson and is identical to this:

http://www.hendrickson-intl.com/products/product_detail/has_tandem.asp

Those U bolts are tiny compared to the ones on any of the Mack camelbacks.

If the U bolts have been on there a while, tightening may be impossible, and the U bolts may need to be torched off and replaced, then tightened properly, and retightened after running it for a day.

I also use a 3/4 impact @175 PSI air pressure and tighten as tight as it'll go, whack the tops of the U bolts with a sledge a few times, then tighten some more till they don't tighten any further.

.

Herb,.......I believe they call that AIR FORCE TORQUED.....where you tighten them until they break then back off a quarter.

mike

Herb,.......I believe they call that AIR FORCE TORQUED.....where you tighten them until they break then back off a quarter.

mike

Speaking of "backing off a quarter".......

Back when I was in school I remember a kid in my class explaining the "proper" way to adjust rocker arms on a small block chevy:

"With the engine idling, tighten the adjusting nut down until you hear the valve hit the piston, then back off a quarter turn".

I'm glad he never worked on anything of mine! :loldude::pat:

"If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

Speaking of "backing off a quarter".......

"With the engine idling, tighten the adjusting nut down until you hear the valve hit the piston, then back off a quarter turn".

Oh my... :wacko:

Ever wonder how a blind person knows when to stop wiping?

gallery_1977_876_21691.jpg

I remember an idiot in auto mechanics class explaining that when he changed oil he would run the engine at idle without oil, (drain plug out of pan) for 30 seconds to purge the internal oil passages of used oil.

He was actually worked the lube rack at K-Mart in those days.

I think he is now an analyst for NASA doing trajectory evaluation using liquid propellants.

Rob

Dog.jpg.487f03da076af0150d2376dbd16843ed.jpgPlodding along with no job nor practical application for my existence, but still trying to fix what's broke.

 

 

After the heavy rains the past few days, had to check up on all the drivetrain and other stuff. Noticed one of the wipers was acting funny. Check it out and the outside nut is stripped. Where is the motor to replace the shaft also, ? I believe its under the dashboard somewhere. Project for Mon. or Tues.

If I wasn't working, things wouldn't break.

Success is only a stones throw away.................................................................for a Palestinian

Tom,......I know where you heard that..............................from somewhere in Farmington, IL.

mike

could be, there's some very smart people in Farminton, Il. Well, at least one-i'm not sure about the rest of 'em.

Producer of poorly photo-chopped pictures since 1999.

Herb,.......I believe they call that AIR FORCE TORQUED.....where you tighten them until they break then back off a quarter.

mike

I had that all wrong. I thought it was "stop a quarter of a turn BEFORE you wring it off".

Producer of poorly photo-chopped pictures since 1999.

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