Best Place to Put Jack/Stands

[C. M. Wolf]

Me, when I'm doing a brake job, I jack the whole truck up,(mostly because I wish to work all 4 wheels at the same time). So I jack-stand the frame ends & add some heavy wood blocking under center frame for 'insurance'. (..and I hate 'jack-dents' on any body panels or parts).

Certainly make sure it's very stable on the jacks or don't leave it or get under it in any way.

Michael

[Tx Firefighter]

You seldom see warped drums or rotors on these trucks. You're most likely to need them machined due to damage from brakes being run down to the metal rather than warping.

It's virtually a moot point.

[pbajwabb]

So I got everything off and found out why the brakes were a bit touchy. The shoes were basically non existant but luckily the drums do not seemed ruined, there arent any deep grooves, I can feel a little bit in there but it think sanding it will get it off. If its too bad and the shoes wear quickly oh well - lesson learned and Ill upgrade to disks or new drums.

I have to put it all back together in the morning and I am not looking forward to it, I have a feeling it will be much harder than taking them off.

Ill keep you posted, the Haynes I picked up was very helpful.

[litew8]

Did a little reading and it seems like there is no such thing as actual warping of rotors. It's the uneven build up of pad material deposits that cause what feels like warping.
Read that article I posted up-thread, it mentions how to break-in new pads and/or rotors.
Turning your rotors isn't all that good, it reduces the thickness needed to dissipate heat properly in the end.
My previous comment about checking for warped rotors would still stand though, only that your really checking for unevenness caused by the worn pads.

[Tx Firefighter]

Originally Posted by litew8

Did a little reading and it seems like there is no such thing as actual warping of rotors. It's the uneven build up of pad material deposits that cause what feels like warping.
]

That is absolutely incorrect. Rotors do warp and warp often. We are fortunate that these old trucks we build have very substantial rotors and they seldom warp, but all vehicles are not so lucky.

Many cars, you can install a brand new rotor that is perfectly true, and over torque the lugnuts and you'll have a warped rotor. Never having applied the brakes a single time, the rotor is already warped. Many a tech with his shiny new Billy Badass impact gun has ruined rotors upon installation when installing the wheels. I've worked in shops full of those guys. They turn a simple brake job into a train wreck because they can't figure out why the new brakes pulse. It's the 350 ft/lb of torque that they tightened the lug nuts to. That's why lug torque is so critical nowadays compared to yesteryear when you could bang them down real tight and never have any troubles.

[litew8]

Originally Posted by Tx Firefighter

That is absolutely incorrect. Rotors do warp and warp often. We are fortunate that these old trucks we build have very substantial rotors and they seldom warp, but all vehicles are not so lucky.

Many cars, you can install a brand new rotor that is perfectly true, and over torque the lugnuts and you'll have a warped rotor. Never having applied the brakes a single time, the rotor is already warped. Many a tech with his shiny new Billy Badass impact gun has ruined rotors upon installation when installing the wheels. I've worked in shops full of those guys. They turn a simple brake job into a train wreck because they can't figure out why the new brakes pulse. It's the 350 ft/lb of torque that they tightened the lug nuts to. That's why lug torque is so critical nowadays compared to yesteryear when you could bang them down real tight and never have any troubles.

Are you sure it isn't uneven torqueing and/or over torqueing. There's an order. Not that it matters, if you've experienced it yourself. I'd think over torqueing alone would cause the rotor to crack before warping, but I don't know much. In my defense (as if I care), I did say "seems like" e.g. not the gospel truth.

[litew8]

Originally Posted by Tx Firefighter

Many cars, you can install a brand new rotor that is perfectly true, and over torque the lugnuts and you'll have a warped rotor. Never having applied the brakes a single time, the rotor is already warped.

I don't understand this comment. Warping is defined as something that is twisted, physically. You're saying over-torquing (alone) the lug nuts can warp (twist) the rotor. Doubt it.

When actually, the term warping (generic reference to the problem) refer to uneven wear. Uneven wear can only occur if the vehicle is being driven and brakes are being applied. Warping and uneven torquing of lug nuts aren't the same thing - cause and effect.

[Cape Codder]

I don't let anyone else work on my truck, but the labor rate around here starts at 70.00 and goes to 120.00 at some dealers. Get into European dealers and it goes higher. And no I don't turn mine anymore as I buy wholesale. But I still don't replace unless there is something wrong with the old ones.

[C. M. Wolf]

Originally Posted by Cape Codder

I don't let anyone else work on my truck, but the labor rate around here starts at 70.00 and goes to 120.00 at some dealers. Get into European dealers and it goes higher. And no I don't turn mine anymore as I buy wholesale. But I still don't replace unless there is something wrong with the old ones.

Same here for letting someone else work on my truck.. but I've found too many mechs out there that try to treat people like idiots by doing things on the vehicles that simply DON'T need repair.. "Oh yeah buddy, that tapping noise is a rod slapping, need a new engine" (..so I adjusted or reworked the heads some & drove down the road telling others to stay far away from that guy!)

AC-Delco, Lockheed, TRW, Etc... don't give me no crap about the 'good ol' days' & insist on selling me some 'south-o-the-border' parts because the dealers can make a bigger profit!



Michael

[1969_CM2590D]

As far as where to put the stands, I place them in a flat, stable area on the frame next to suspension attachment points. So TxFirefighter has it right about the front. for the rear, I'd put stands close to the trailing arm attachment point. For leaf springs- to the rear of the front spring attachment and to the front of the rear spring attachment.

With the VW, I put the stands under the torsion bar tubes. The Corvair gets them under the front axle assembly and the rear subframe.

About the scam of "warped" rotors. Years ago a mechanic friend of mind told me of visiting a Famous Muffler Shop. One of the techs there showed him a room with used rotors, all marked and cataloged for turning. Of course they were perfectly good with plenty of life left in them- customers had been duped into buying new ones. It's up to you for figure out if they were reconditioned and sold off as such- or put on the next car they would fit on as "new" rotors.

If one lives where it is hot most of the time, and does a ton of stop and go driving- that is what's most likely to mess up rotors. So will an incredible amount of hard, erratic braking.

A good shop will just turn them enough to even them out. Most turn them to the legal limit, making them too thin for a second or third turning. I had some turned about 15 years ago (by the way- the last time I did it) by a shop that knew what they were doing- it was $40 an axle. Both sides MUST be turned to an identical thickness- rotor or drum.

Fewer and few places are turing drums. Most of them today go on FWD cars, are small, are "along for the ride", and are cheap throwaway items (so are rear discs for that matter). Rear drums/rotors don't take the stress of the fronts and are designed accordingly. So the demand for drum turning has declined over the years. I don't know of a good place locally that does drums anymore.

After I heard about the muffler shop, I asked many I knew about turning. No one who who did their own work fooled with it, unless a disc or a drum had a serious shimmy to it. So now when I do pads/rotors- if the stopping is smooth. I don't bother with turning or replacing.

Now when the company car goes in for brakes, the fleet service invariably pays for new rotors- but hey, I'm not picking up that tab!

[litew8]

How Lateral Runout Develops - YouTube

[litew8]

"LRO is most often the result of small inconsistencies in the rotor and vehicle hub that are magnified when combined. LRO can also be induced by uneven wheel torque, improperly adjusted or worn wheel bearings, corrosion, or damage from hitting a curb or pothole. Any of these conditions can easily lead to a poor brake performance that will worsen over time. LRO within the specified limits helps to reduce the off-brake caliper drag by pushing the piston back. Due to the side-to-side motion of rotor, it hits the pads back from contact of the disc and pushes back the unretracted piston. The general specification for lateral disc run-out should be less than 0.15 mm but should not exceed 0.20 mm even in exceptional cases."

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LRO isn't a 'warping', it's uneven wear; thickness variations.

[Tx Firefighter]

Let me illustrate it this way.

In mid 1995, I quit the dealership and took a job with the Postal Service until 2001. I did fleet maintenance on mail trucks at the Ft.Worth VMF where we cared for 800 odd light trucks in the district.

To say we did a lot of brakes would be a fantastic understatement. Some mail trucks on hard routes would go through a set of brake pads every 45-60 days. The shop as a whole went through pallets full of new brake pads regularly. There was never a time when there wasn't five or more brake jobs being done concurrently in the shop.

You could take a brand new rotor out of the box, spin it on the brake lathe to assure it's true and install it onto the truck. Install wheel and tighten the lugnuts retard tight with a big Ingersoll Rand 1/2" impact. Then, back it out of the shop, put it in drive and drive 100 feet and apply the brakes. Pulse, pulse, pulse and shaky steering wheel. The brakes had never been applied or heated up and already the rotors need truing. It's from over torquing. It deforms the center hub section of the rotor and conversely the rotor. You could then remove the rotors and put them on the lathe and you'd get a zik-zik-zik sound as they were warped and needed cut to make them true again. I'm talking trucks that never got further than rock throwing distance from the service bay. The brakes hadn't been over heated or even applied more than once at low speed. The guy backs it out of his bay and doesn't even park in on the line before he pulls it back inside muttering about defective rotors

When things were done correctly and lugnuts torqued properly, never an issue and the brakes would be Cadillac smooth.

These are things we had to figure out because we had a couple of real chuckle heads that worked there and could screw up even the simplest procedures. It finally deteriorated to where we had to oversee the torquing to assure one of the knuckle draggers didn't ruin a set of rotors and cost us lost time in fixing it properly.

[fast&low]

You're taking this way too far
There's just no way you can compare a daily vehicle or a weekend toy to a service vehicle that the brakes are abused daily by stop & go all day every day like a mail truck.

[fast&low]

Yeah it's called the defective rotor

[pbajwabb]

Hey guys,

I wrote up a little guide about doing the brakes, can someone check it out for accuracy?

I dont know why my photos aren't loading but it is pretty thorough.

http://67-72chevytrucks.com/vboard/s...d.php?t=623985

[fast&low]

Yeah okay?
If you are looking for an argument you won't get it here and especially at this time in the morning.
By all means turn your rotors & torque your lug-nuts if your car not mine!!

[sKnNyPpY]

Originally Posted by fast&low

Yeah okay?
If you are looking for an argument you won't get it here and especially at this time in the morning.
By all means turn your rotors & torque your lug-nuts if your car not mine!!

You're new here aren't you? I would dial it down a bit.
http://67-72chevytrucks.com/vboard/s...d.php?t=614460

[fast&low]

You guys are something else I tell you what
And what let you know that I was new hear something like my join date
Leave it alone already it's too early please move on because I will

[Tx Firefighter]

This one has run its course for me. I don't get down in the mud on Internet forum boards anymore.

Original poster, I think this thread should hold some sort of record on how profoundly a thread has derailed. We started out with jack stand placement and deteoritated into slinging mud about brake tech. I apologize for contributing to your thread making such a drastic turn.

Back on topic, always remember that your jackstands should be placed under the truck such that they are on a flat surface and not subject to slipping when loaded. Personally, in the rear, I place my stands under the axle tubes. My own jackstands are saddle shaped on the top, as are most stands, which cradle the round axle tubes very well.

Also, once the truck is settled down onto the jackstands, take a second and verify that the stands are sitting flat on the ground. Sometimes they get slightly loaded laterally and you'll notice all of the feet of the stands aren't touching the concrete.

And, most of all, once you've got it settled down, take your shoulder and give the truck a good push to make sure its stable. Shake it, linebacker shove it, whatever, just make sure its stable. I've spent 25 years working underneath cars on stands nearly daily and I almost got bit four years ago when I was building my 63. I heard the truck move and thankfully I was on a good creeper on clean concrete so I was able to get out from under it before it fell to the ground. I would have absolutely been killed had I reacted about 1 second later. And, I was here at the shop alone so I'd have laid there until my wife got home several hours later. Bad deal. I renewed my diligence at the safety aspect within that one second. A lesson learned I'll never forget.

[sKnNyPpY]

Hey, I'm new too. Just been here a little longer than you. Kevin is an expert at these trucks and been real helpful to hundreds of builds and thousands of threads. Just seems silly to argue semantics with him and way off the original post as well. Good luck.

[GASoline71]

Wow... the main reason to have the drums and discs turned is to have a surface for the shoes or pads to wear in to. So they won't glaze over and cause squeals and insufficient braking. Nothing like ruining a new set of pads or shoes.

It usually costs about 50 bucks to have all 4 drums, or 2 drums and 2 discs turned. It's part of the brake job as a whole. The shop will also check the thickness of the rotor or drum and see if it's service life is over.

Meh... it's your truck... do as you like.

Gary

[litew8]

Last comment from me. What TxF mentioned: "It deforms the center hub section of the rotor and conversely the rotor. You could then remove the rotors and put them on the lathe and you'd get a zik-zik-zik sound as they were warped and needed cut to make them true again." has absolutely nothing to do with actually 'warping' of a rotor. What he is describing is his co-workers DAMAGING the rotor, giving the impression of actual warping.

Warping is a generic word used to describe Lateral Runout (as shown in the video above). It is cause and effect. Uneven torqueing of the lug nuts will result in LRO. Over torqueing and actually damaging the rotor isn't the same thing - it's far more extreme.

[GRX]

Threads like these always make me wonder ... how many people actually test for rotor run out with a dial indicator? Not enough that's for sure.

[litew8]

Originally Posted by GRX

Threads like these always make me wonder ... how many people actually test for rotor run out with a dial indicator? Not enough that's for sure.

YouTube