Recovered my M927 truck

It's a common misunderstanding and it's an easy thing to get wrong, so don't feel bad about it.

I have a funny story about a personal experience with this phenomenon, concerning my MG Midget and the old NJ state safety inspection procedure, and me spinning off into one of the turf farms on Meadow Road south of Princeton, but I'll spare everyone the bytes. d8-)

"PrecisionmachinisT" wrote in message news:xfGdnVZQCsvFdC7MnZ2dnUVZ snipped-for-privacy@scnresearch.com...

Think about what will happen if you brake too hard while turning, for example if a kid unexpectedly runs into the intersection in front of you.

If you've never raced on dirt or ice, the answer is that locking the fronts makes you slide straight ahead until you let off, locking the rears makes you spin out of control unless you've practiced a lot. The dynamics are much more evident on a dirt bike with separate front and rear brakes that you have to learn to operate differently, while clutching and downshifting. jsw

I've seen it because the pad material on the sorry-ass drums is also sorry whereas the disk pads are at least ok...I was hypothesizing something of that nature combined w/ Iggy's propensity to not brake hard might generate his observation...when asbestos first went away there were some really poor pads for awhile, indeed, although they've done pretty well since. Brakes go in a hurry on trucks/cars here 'cuz of all the sand/grit that gets in them from the dirt roads that cuts rotors/drums up in hurry. Not unusual to have to replace the metal parts as just can't face them enough to last life of rest of vehicle before run out of material...

True of course.

Nope. Half true. When the brakes are applied the vehicle weight transfers toward the front of the vehicle. Thus with a higher percent of the vehicle weight on the front wheels there is more traction and thus you can apply more braking force.

You can prove this theory easily with a bicycle or a motorcycle. make a stop with only the rear brake and than repeat the maneuver with only the front brake.

Exactly :-)

On 6/8/2013 8:07 PM, PrecisionmachinisT wrote: ...

As has been pointed out, weight transfer from the momentum transfer during deceleration means front can transfer more force to the road than rear (relative to static balance at rest/zero acceleration).

There's a nice explanation of the physics w/o getting excessively mathematically involved at the following link...

I've also got too many things going on at the moment but I'll just say that the ABS performance on my 98 silverado is either broken or is so badly engineered that when it activates, it takes about 3 times as long to come to a complete stop when driving on snow or ice...I know this because I can pull the electrical plug from the ABS system and actually test with the ABS disabled.....for this reason, I've taken to unplugging the system during wintertime.

I've had only one car with ABS -- my Hyundai Sonata -- and although I like it, and I'm glad my wife drives that car in bad weather, I'm pretty sure I could beat it. It seems to be better at maintaining control than at actual stopping distance.

But I have a pretty sensitive foot, having learned trail-braking back when I raced, and I used the Moss method of initiating a turn with the brakes when I raced on ice at Rose Lake, MI.

Maybe, or maybe I'm deluding myself that I could beat it. I should try it sometime.

My brain isn't programmed for ABS so I don't/can't use it like it was intended to be. Sometimes a four wheel lockup is helpful, most of the time it isn't but with ABS doing the thinking you lose these other options that some of us have developed, sometimes called "muscle memory".

I don't want (nor have) a vehicle with ABS, traction control, airbags, rear view camera, air conditioning...

I urge you to change your opinion on airbags.

Virtually EVERy car or truck with ABS will take significantly longer to come to a stop under "normal winter driving conditions" I like to say all ABS does is help guarantee you hit what you hit SQUARE ON. (instead of somewhat sideways)

It's a good bet with your experience you could outbrake ABS by a significant margin - even with "old guy" reflexes!!!!

I've got a story I could tell about DOT safety lanes and a Morris Mini that relates to brake bias too.

I'll tell it if anyone asks.

Yes, I call them Anti-Stop brakes! I could have avodid hitting a deer once, but no.....

MikeB

IIRC snow and gravel are something that ABS doesn't go well with as the wedging actions of snow and gravel under a locked wheel help slow the vehicle and that doesn't occur with ABS causing an increased stopping distance. Some early ABS cars allowed for it to be turned off manually for these reasons but I suspect laws mandating ABS will have removed that option. So maybe maintaining a rotating wheel and preserving some steering is seen as the best compromise.

He doesn't need them if he never hits anything, and if he always wears his seat belts properly the advantage to airbags dissapears pretty quickly even in a moderate colission. If he is under 5'4" the airbags become a serious liability.

In a minor front end colission you can write off a GM compact or intermediate car without doing ANY body damage in a 7mph frontal colission. The cost to replace the air bags, instrument panel, (dash) air bag controls and windsheild excedes the salvage value of a 5 year old car in many cases. If you manage to damage the bumper, grille, or front header panel it's pretty well a certainty.

As for anti-lock brakes they help maintain control in a panic stop on bare or wet pavement when they work properly - but are useless on light snow covered or slushy roads, and even worse in heavy wet snow or snow-pack. And they are expensive to trouble-shoot and repair, as even most mechanics don't understand how they work adequately.

I've had ABS equipment failures cause total loss of front braking, total loss of rear braking, unpredictable pull to either left or right under moderate braking at highway speeds (which could get real ugly in a light rain after a long dry spell - rubber dust and oil emulsion making the roads slick - and brake grabbing) - and NONE of the problems could be diagnosed by the dealer's diagnostic code readers.

I found and repaired each of the problems with a combination of deductive reasoning and a good helping of LUCK. ( and the outlay of a fair number of bucks for required replacement parts in 2 cases )

I'll ask. Please tell us the story, Clare... ;>)}

Check the TSB's, when I was working on the '99 Suburban brakes, I found a few bulletins about a brake proportioning problem that they only fixed if they got complaints. There might be a TSB on the ABS.

OK. Phil asled.

In 2003 I bought the wife a 1997 Saturn with 78,000 miles on the odo for $1500 in georgious shape. 6 yr old car that had been stolen just for the airbags. A local guy was buying the cars as salvage for about $800, doing a wax, oil change, new floor mats etc etc and selling them after advising the buyers they were "salvaged" and no airbags were included. He had me sign a statement to that effect. Shrug

I think he must have sold at least 100 of these Saturns over a couple years out of his farm. All nice cars. The wife currently is still driving it with 257,000 (miles) on the odo...with no serious issues noted.

Seems at that time the Saturns air bags were in great demand and stolen ones were getting upwards of $1000 each...x (2). I should try to find out if the guy is still selling similar cars.....shrug.