had an oh crap moment today.

Is that like a high school auto tech class?

Downshifting vehicles is a widely used practice. Even automatics do it.

 

Tech School

 

And limiting your speed on hills ?

 

In that case, it is ok to downshift. I also agree that rev matching will greatly reduce the wear on the clutch. Practice makes perfect. Then again, why not just use the brakes for their intended purpose? As I said, I'd much rather pay for brake pads than a clutch disc.

I get it though, no one is going to change the way they've always driven based on a random internet post, so I'll let it go as agree to disagree.

 

$10 you own an auto trans

 

You're doing the same thing in both instances

 

If you do it wrong, I can agree. Re-read post 17 on how to do it right.

What you want to do is take advantage of engine braking, at least in certain situations.

In city driving it's not needed, unless you just want to practice. You can brake until RPM gets down to a level that you'd not accelerate in whatever gear you are in, put it in neutral, and finish your stop with the brakes.

In racing it's brake only, before your turn, select gear to come out of turn with, rev match, engage clutch and hit throttle. Engine braking in racing is a time killer.

In a panic stop, 'both feet in' is the order of the day.

But on those long grades, where the sign says 'use lower gear', it's a brake overheat/fail precaution, using the engine as the main braking. And to get in that lower gear does not require clutch damage, again, see post 17.

And no, it does not put 'undue strain on the engine' as you comment in in another post. Well, again, not if done properly. If you pick the wrong gear to downshift to, and over rev the engine, yep.

And for those of you who might be going to jump me re ECU rev limiter protection, unless Toyota is different, it doesn't work on an unloaded motor downshift. The limiter is a fuel cut, and when you lifted out of the throttle, you already did that. Seen more than a few motors over revved by going from 5th to 2nd when they meant to hit 4th.

 

Even the 5 speed autos downshift for you to control speeds on hills. Though they don't do it quite like an Allison transmission does.

Whenever someone says downshifting a manual is bad I immediately know two things. They never have driven a performance car or motorcycle, and they've never driven a big truck with a heavy load.

When you rev match on downshifts you are matching engine and transmission speeds, so the clutch and driveline can mesh smoothly. There are even manual transmission cars and motorcycles that rev match for you know.

This is not a harmful practice when done correctly.

 

i like lurking around. have followed the main abs thread for a while. did the mod a long time ago because i experienced this on a regular basis. just like royden, i could duplicate the abs acting up.

i have michelin ltx/ms2 shoes. on a completely dry road, i can drive over a crack (you can feel the tires dropping off the higher part of the road, over the crack, to the lower part) and the abs kicks in. it pulses and i continue to roll forward, able to steer, but unable to brake. completely impotent and flaccid braking. non-existent at that time, and dangerous.

exactly this. after installing the mod, i've been fine and can stop easily. now i don't have to shit my pants while flying through the intersection without braking power. thanks, abs mod!

 

So that is why the clutch in my last truck only lasted 20 plus years. It may be longer as I sold it and it was still going strong and not slipping. I was down shifting and using the engine to brake.

I'm sorry, but I have been driving since I was 14 years old, I'll be 60 next month. In all that time I have been using the engine and down shifting before ever touching the brakes. It doesn't hurt the clutch or engine at all. Anyone that says different just doesn't know what they are talking about.

Now if you keep your big old foot on the clutch pedal while doing it is a whole other story and subject all together.

 

Meanwhile, back to the OP topic, I believe the ABS system has a little to be desired. At my age I've owned several different makes of cars with ABS. Toyota's design is one of the worst. J.M.H.O.

 

Back in the other ABS Thread I mentioned how hypersensitive ABS was in my old 08 with the Original Rugged Fail Tires and swapping them out made a huge difference. But after thinking about that for a few days I remembered a situation when I was approaching an intersection while the road was just slightly damp, clutch in and brakes on, as I got closer to the intersection my right front tire went into a slightly dropped down manhole cover, ABS kicked in and the truck just rolled forward a good 25 or 30 feet stopping just before going out into traffic. Anytime I ever went that way after that I always steered left or right to go around that manhole cover

 

you need to go back to class "just saying"

 

& ABS strikes again....I absolutely hate that shit & has no place in the automotive industry as far as I'm concerned & for sure around here it's caused more wrecks than it ever prevented (if it ever did) Offroad it's a nightmare as well, maybe even a bigger issue. Nothing sucks like hitting the brakes & actually gain speed..fuck that shit...

 

my 02 has abs and still locks up.

 

So in a situation where you could have died due to possible malfunctioning brakes, why not get out and check if there was black ice? Could have confirmed or denied this entire debate (with respect to your specific incident) in a matter minutes.

 

I have no idea about the other guys, but strictly in my case it happened in Late Spring, Early Summer so there was no Phantom Black Ice around.

 

Then you're lucky , it's malfunctioning ......

We very rarely have black ice here but from what I've been told & have read most people don't know it until their in it...

 

The ABS is total shit on this truck and the local master mechanic here agrees. Owned for 1.5 years now and had 9 situations since new. 7 at complete stock. All with no snow and 2 with wet pavement at stock. ABS has kicked in while cornering which takes away throttle control and wants to send you straight. Obviously a bad thing in corners.

And before you question my driving ability, I have 0 accidents on road, have been driving for 29 years, CDL owner/ op for log trucks driving during foul weather in WA,OR, and CA. I've seen it and driven in it with a couple million miles experience. Computer control is bullshit. Even have the college degree on mechanical electronics that tells me if it is electronic, it is designed to fail. If you question that.....why does your tv, washer, toaster,microwave, etc not last even half the life that your mothers did?

ETA: Not saying the truck is shit cuz I love it, but I've never had a computer try to control my driving before this. And that is what is bullshit.

 

Exactly, also known as "planned obsolescence ".. & I'll add that when I decide (not a computer) to hit the binders ,I want to look in my rear view & see 4 skids, oddly , the only time my brakes are working as they should is when the ABS light is on.