I 70 sucks

[jmeb]

Full sixe trucks are different. Jake brakes save lives.

dm

Full-size truck = F150/Silverado 1500s. Engine braking to reduce wear on pads and rotors. No Jake brakes on such vehicles.

 

[tball]

Well you wouldn't want to be doing anything silly engine braking in a front or rear wheel drive vehicle in slippery conditions.. too hard to modulate lock up except at very slow speeds.

Yes, don't downshift to slow down when it is slippery. Use your brakes to slow down, then downshift to hold the speed on a downhill grade. It applies to four-wheel drive too.

 

[tball]

The reason why I've replaced several sets of friends' warped front rotors in the last few years is because they overheat them on long descents from the tunnel. There is no other reason you'd see such frequency of warped rotors among a wide variety of otherwise fine, modern cars besides heat.

After countless "warped" rotors from driving I-70, I think I've found how to avoid the expensive annoyance.

It turns out the rotors are not actually warped. The pulsing of the brakes is from uneven deposits of brake pad material from when the brakes are hot. Here's an article that describes the problem:

Nuts & Bolts: Warped Rotor Myth

I have a 2003 GMC 3500 single-wheel truck that I use to haul a pretty big toy hauler. I’ve weighed the whole thing and it’s heavy, but I’m within the weight rat

www.motortrend.com

Here's a solution from that article:

"Another thing you can do is avoid being on the brakes with the vehicle stopped when you know the brakes are hot. Shift it into Park while you wait for the light to turn at the bottom of the off ramp and take your foot off the brakes. This helps avoid leaving a footprint of the pad on the rotor."

I-70 is brutal, given how often you have to brake to a stop on a downhill grade from high speeds due to traffic. I'll try to slow early enough that I don't have to come to a complete stop when possible.

 

[scott43]

After countless "warped" rotors from driving I-70, I think I've found how to avoid the expensive annoyance.

It turns out the rotors are not actually warped. The pulsing of the brakes is from uneven deposits of brake pad material from when the brakes are hot. Here's an article that describes the problem:

Nuts & Bolts: Warped Rotor Myth

I have a 2003 GMC 3500 single-wheel truck that I use to haul a pretty big toy hauler. I’ve weighed the whole thing and it’s heavy, but I’m within the weight rat

www.motortrend.com

Here's a solution from that article:

"Another thing you can do is avoid being on the brakes with the vehicle stopped when you know the brakes are hot. Shift it into Park while you wait for the light to turn at the bottom of the off ramp and take your foot off the brakes. This helps avoid leaving a footprint of the pad on the rotor."

I-70 is brutal, given how often you have to brake to a stop on a downhill grade from high speeds due to traffic. I'll try to slow early enough that I don't have to come to a complete stop when possible.

Yes it's also often because the tech doesn't clean the hub/rotor/wheel interface. Over time they wear unevenly. Improper torque can also cause distortion when they heat up.

 

[scott43]

Yes, don't downshift to slow down when it is slippery. Use your brakes to slow down, then downshift to hold the speed on a downhill grade. It applies to four-wheel drive too.

And really any car built in the last ten years will have goodies to help keep things together and out of the rhubarb..

 

[James]

Some cars in sport mode will automatically downshift going downhill if you brake enough. Doesn’t take that much braking.

As for over heating passenger car brakes, I smell them all the time. Hike up any Mt Road where cars go.
“This car climbed Mt Washington” stickets on bumpers - best to stay away. You know the brakes are shot.

Speaking of Mt Washington, I doubt Travis Pastrana left it in 6th gear on the way down and just used the brakes the whole way. Even if he doesn’t pay for them. No control in 6th! Keep the drivetrain loaded.

One is supposed to downshift before the hill. Not in the middle, on slick roads.attempting to dump speed.

 

[Dave Marshak]

One is supposed to downshift before the hill. Not in the middle, on slick roads.attempting to dump speed.

So have we reached a consensus that a lower gear to keep speed under control is acceptable but aggressive downshifting to dump speed is an ineffective way to contol your car in slick conditions? That's where I was when I started this whole dispute, even if I don't expressly state that.


dm

 

[scott43]

So have we reached a consensus that a lower gear to keep speed under control is acceptable but aggressive downshifting to dump speed is an ineffective way to contol your car in slick conditions? That's where I was when I started this whole dispute, even if I don't expressly state that.


dm

The devil is in the details??

 

[Eric@ict]

I'm not sure what happened this weekend. I-70 had an accident and they were re-reouting through Loveland pass. Then another accident on the Dam Road.
Then another accident on I-70.

Adding to that, a cyclist got hit and killed on the stretch of road above Silverthorne on US-6; then another car accident on US-6.... (not on same weekend, but just mentioning).

I'm fairly sure nothing is going to fix the I-70. First thing to fix is the declining reaction times even amongst the youth. I've been noticing it even on the bike path; it's like they are living life on a 500ms+ latency; almost guaranteed death unless you have a ton of electronic systems compensating.

Leaf Peeping. It was a mess on 285 also. Traffic was backed up from Kenosha pass to Jefferson. I see lots of people on their phones while driving, thru our area the signal sucks so you see ppl paying attention.

 

[Eric@ict]

Now you’re just making stuff up. Overheating brakes isn’t really a thing for passenger cars anymore.
Downshifting to control speed is never necessary anymore, and never provides better control than brakes, at least not with modern cars.

dm

Sure it is, that is what warps rotors. Still an issue in todays cars.

 

[Eric@ict]

After countless "warped" rotors from driving I-70, I think I've found how to avoid the expensive annoyance.

It turns out the rotors are not actually warped. The pulsing of the brakes is from uneven deposits of brake pad material from when the brakes are hot. Here's an article that describes the problem:

Nuts & Bolts: Warped Rotor Myth

I have a 2003 GMC 3500 single-wheel truck that I use to haul a pretty big toy hauler. I’ve weighed the whole thing and it’s heavy, but I’m within the weight rat

www.motortrend.com

Here's a solution from that article:

"Another thing you can do is avoid being on the brakes with the vehicle stopped when you know the brakes are hot. Shift it into Park while you wait for the light to turn at the bottom of the off ramp and take your foot off the brakes. This helps avoid leaving a footprint of the pad on the rotor."

I-70 is brutal, given how often you have to brake to a stop on a downhill grade from high speeds due to traffic. I'll try to slow early enough that I don't have to come to a complete stop when possible.

Rotors do warp. Its easy to see when you turn them. Material transfer does happen when hot and you leave the brakes engaged as described.

 

[Jerez]

Consensus. Thank you!

 

[James]

So have we reached a consensus that a lower gear to keep speed under control is acceptable but aggressive downshifting to dump speed is an ineffective way to contol your car in slick conditions? That's where I was when I started this whole dispute, even if I don't expressly state that.


dm

Is this where we say, “Nope, not even close.”?

 

[Bozzenhagen]

You can aggressively downshift smoothly. Probably not with an automatic?
DSG rev matches downshifts for you.
Manual transmissions come with an auto-blip feature now on certain cars, or you can do it yourself (rev-matching).

I was going 70mph in 3rd gear today down the hill to Georgetown.
I double clutch from 2->1 all the time at high rpm (not high enough to exceed redline and kill my engine).

Brake then downshift, or just downshift, or brake and downshift at the same time (heel-toe).

 

[Rich McP]

I agree with that. Engine braking as your first or only choice for slippery road conditions is obsolete.

dm

I hate to say that you are talking out your azz, but you are. Your statement in the vacuum of 2022 vehicles might have merit, but in the statement as a general rule is useless. All you need do is look around at the variety of rides running up and down I70. In case you are confusing what everyone here is advocating with something in your mind, what's suggested here is to come out of the tunnel at a safe speed, select a gear that would have you running too slow with your foot off the throttle, and modulate the throttle to speed up to the decent speed you want. I fear you are thinking people are saying, "If you are going too fast, slam down a gear or two." They are not saying that. Engine braking on a long steep slick grade is about using your engine and trans to keep you from EVER going faster than you and the conditions can handle.

 

[slowrider]

You can go down a grade a million times too slow. But only once too fast.

 

[mikel]

So winter season is upon us. Maybe there should be a "How many Days" thread for I70 closures. Ski season is just getting started and so is the I70 safety closures. And not just for an interstate covered in soy sauce. (yes that really happened). Time for people to realize it's transitioning to winter in the mountains and summer tires won't cut it.

 

[Tricia]

So winter season is upon us. Maybe there should be a "How many Days" thread for I70 closures. Ski season is just getting started and so is the I70 safety closures. And not just for an interstate covered in soy sauce. (yes that really happened). Time for people to realize it's transitioning to winter in the mountains and summer tires won't cut it.

Did I hear that there was already a massive accident near Idaho Springs?

 

[tball]

There was a 100-car accident in the heart of Denver this morning:

Video: Drone shows scene of 100-vehicle crash in Denver

FOX31’s drone flew over the scene of the crash on 6th Avenue and Kalamath Street.

kdvr.com

It looks like CDOT didn't properly de-ice the elevated portion of 6th ave. Snow tires are not only useful in the high country.

I'm noticing more and more that CDOT seems to do a minimal job when the forecast is for the sun to come out and melt the roads, like this morning. Either stay home until the sun works its magic, or have some true winter tires that can stop on ice.

 

[mikel]

Did I hear that there was already a massive accident near Idaho Springs?

I didn't know about the the Denver accident. Not sure about Idaho Springs. It has been pretty bad between Vail Pass and Loveland Pass.