Brake Issue While Mountain Driving (1 Viewer)

[TLCStonks]

So I was driving the scenic byway from Santa Fe to Taos which has some decent elevation changes but nothing that seemed extreme. About halfway through a 1.5 hour drive I was on a downhill turn and pressed the breaks and when I let go the brakes grabbed about 4 more times; its hard to say but I think it was coming from the left rear since I did have some jerk in that direction. I'm pretty new to the vehicle and haven't tested driving in the mountains but after that experience I started to use engine braking a lot more often to slow me down thinking it may have been due to overheating.

Any thoughts on what might have caused this issue? Do I need to lean on downshifting a lot more while mountain driving? Is there anything I can do to improve brake performance to minimize this?

 

[awesomeissquid]

When the incident occurred was there any beeping or lights flashing on the dash?

 

[badlander]

Check your emergency brake system. If dragging at all the pads can tend to grab in a cyclic rthym.
How do I know this? I forgot to let off the brake one time and about 1/4 mile down the road this pounding started and it was so bad I thought for sure I had a flat tire. Pulled over to check and the tires were fine. Then I noticed the brake light on. Let it off and all was fine again.

 

[TLCStonks]

When the incident occurred was there any beeping or lights flashing on the dash?

No, no lights or beeps

Check your emergency brake system. If dragging at all the pads can tend to grab in a cyclic rthym.
How do I know this? I forgot to let off the brake one time and about 1/4 mile down the road this pounding started and it was so bad I thought for sure I had a flat tire. Pulled over to check and the tires were fine. Then I noticed the brake light on. Let it off and all was fine again.

That is interesting, this particular behavior did seem cyclic for about 4 revolutions. It would make sense since these long hill descents require constant brake pressure at times.

More than anything I'm wondering how the communities brake performance generally is? Would you expect to have to help your brakes with the engine or are you confident taking a mountain pass without any sort of brake issues?

 

[CloudCity]

More than anything I'm wondering how the communities brake performance generally is? Would you expect to have to help your brakes with the engine or are you confident taking a mountain pass without any sort of brake issues?

I have always been in the habit of engine braking on descents so I never really ride the brakes. In the mountains my rig may as well be a manual I am shifting her around so much.

 

[Mike NXP]

No, no lights or beeps


That is interesting, this particular behavior did seem cyclic for about 4 revolutions. It would make sense since these long hill descents require constant brake pressure at times.

More than anything I'm wondering how the communities brake performance generally is? Would you expect to have to help your brakes with the engine or are you confident taking a mountain pass without any sort of brake issues?

I dropped around 4k feet this weekend on a steep rocky road in Idaho and relied 100% on my brakes. They shouldn't fail under most all normal driving conditions. That being said there is obviously a time and place for low gear travel. If brakes got too hot and gave up I think it would result in more of a spongey / faded feel, not a grabbing of the brakes once the pedal is released.

The symptom you described sounds like the traction control kicked in and applied pressure to one of the brakes, I can feel the same type of deal when I try to get the truck to slide in the snow but it goes hand and hand with a "beep beep beep" and the icon on the dash lights up briefly.

I think an e-brake, even if fully applied wouldn't cause the grabbing symptom you described.


You should give the system a once over, check fluid levels, brake conditions, lines, etc. for a good place to start.



Some owners have a brake failure where it will go soft and the brake will go to the floor followed up by a alarm noise but that's a story for another thread
>>Poll on total brake failure in 100 series - https://forum.ih8mud.com/threads/poll-on-total-brake-failure-in-100-series.872498/page-9

 

[RedesKat]

+1 the engine braking. In the auto I always put it overdrive off if im going faster or down to 2nd when I'm going down a big hill. Takes a huge load off the brakes and if you need to brake, combined with engine braking is really effective. If you have the higher speed auto box or manual would probably be easier to maintain a higher speed down a descent

 

[2001LC]

Stating your year, helps! The 100 series 98-99 w/lockes did not have VSC and only rear brake line. We've two variation in master in 00 w/VSC. Some changes on 03-07 vs 00-02.

Using brakes to control downhill speed, is NOT proper driving and can cause loss of brakes and catch them on fire.
In Colorado on I-70 going down HWY passes, we've runaway ramps for those that do. We can spot out-of-staters drivers (flatlanders), even if they've CO plates. How! We see their brake lights constantly coming on, during down hill.

One should always use transmission gearing to control downhill speed. For me it's second nature, and foreign to use brakes to control speed. Brakes are used to slow, when speeds is to high for transmission to shift down into to selected gear or for stopping. When descending very steep terrain, road, HWY shift transfer case to low and granny it down. Stay off the brakes.


But I can't say I've ever heard on brakes grabbing, without pedal depressed. Unless ABS / VSC / TRAC kicking in. Which dash lights and alarm alert one to happening. Could be they were not noticed but can on or not working?

Make sure to test your brakes ABS function, lights and alarm.

Turn key to on. Watch dash light self test. You should see ABS, VSC, TRAC lights and all others, for about 3 seconds.
With key on (engine off) pump brake pedal repeatedly & rapidly. You should hear alarm.
Drive on dirt road at ~35MPH, and brake very hard. You'll heard ABS kick in (crunch, crunch, crunch) to slow faster turning wheels.


E-brake shoes perhaps?
Not releasing E-brake (lost count of how many times I've done that), or they freeze sticking on (I've only seen when iced up)
Not backing off e-brake shoes, before removing rear rotor/drum. Can damage the e-brake shoes retaining system. Inspect them!

 

[Ayune]

We can spot out-of-staters drivers (flatlanders)

You can smell them too. Nothing like the smell of burnt brake pads…

 

[Mike NXP]

Stating your year, helps! The 100 series 98-99 w/lockes did not have VSC and only rear brake line. We've two variation in master in 00 w/VSC. Some changes on 03-07 vs 00-02.

Using brakes to control downhill speed, is NOT proper driving and can cause loss of brakes and catch them on fire.
In Colorado on I-70 going down HWY passes, we've runaway ramps for those that do. We can spot out-of-staters drivers (flatlanders), even if they've CO plates. How! We see their brake lights constantly coming on, during down hill.

One should always use transmission gearing to control downhill speed. For me it's second nature, and foreign to use brakes to control speed. Brakes are used to slow, when speeds is to high for transmission to shift down into to selected gear or for stopping. When descending very steep terrain, road, HWY shift transfer case to low and granny it down. Stay off the brakes.


But I can't say I've ever heard on brakes grabbing, without pedal depressed. Unless ABS / VSC / TRAC kicking in. Which dash lights and alarm alert one to happening. Could be they were not noticed but can on or not working?

Make sure to test your brakes ABS function, lights and alarm.

Turn key to on. Watch dash light self test. You should see ABS, VSC, TRAC lights and all others, for about 3 seconds.
With key on (engine off) pump brake pedal repeatedly & rapidly. You should hear alarm.
Drive on dirt road at ~35MPH, and brake very hard. You'll heard ABS kick in (crunch, crunch, crunch) to slow faster turning wheels.


E-brake shoes perhaps?
Not releasing E-brake (lost count of how many times I've done that), or they freeze sticking on (I've only seen when iced up)
Not backing off e-brake shoes, before removing rear rotor/drum. Can damage the e-brake shoes retaining system. Inspect them!

Were not driving 80k lb. tractor trailers, most of rigs are more than capable of relying on the brakes is all I'm saying. Of course there is a time and a place to use your gears and overdrive to help slow your rig down but my point is although it is proper technique to do so, it's not a necessity under most conditions and shouldn't have anything to do with the current problem in question.

 

[TLCStonks]

Stating your year, helps! The 100 series 98-99 w/lockes did not have VSC and only rear brake line. We've two variation in master in 00 w/VSC. Some changes on 03-07 vs 00-02.

Using brakes to control downhill speed, is NOT proper driving and can cause loss of brakes and catch them on fire.
In Colorado on I-70 going down HWY passes, we've runaway ramps for those that do. We can spot out-of-staters drivers (flatlanders), even if they've CO plates. How! We see their brake lights constantly coming on, during down hill.

One should always use transmission gearing to control downhill speed. For me it's second nature, and foreign to use brakes to control speed. Brakes are used to slow, when speeds is to high for transmission to shift down into to selected gear or for stopping. When descending very steep terrain, road, HWY shift transfer case to low and granny it down. Stay off the brakes.


But I can't say I've ever heard on brakes grabbing, without pedal depressed. Unless ABS / VSC / TRAC kicking in. Which dash lights and alarm alert one to happening. Could be they were not noticed but can on or not working?

Make sure to test your brakes ABS function, lights and alarm.

Turn key to on. Watch dash light self test. You should see ABS, VSC, TRAC lights and all others, for about 3 seconds.
With key on (engine off) pump brake pedal repeatedly & rapidly. You should hear alarm.
Drive on dirt road at ~35MPH, and brake very hard. You'll heard ABS kick in (crunch, crunch, crunch) to slow faster turning wheels.


E-brake shoes perhaps?
Not releasing E-brake (lost count of how many times I've done that), or they freeze sticking on (I've only seen when iced up)
Not backing off e-brake shoes, before removing rear rotor/drum. Can damage the e-brake shoes retaining system. Inspect them!

Awesome! Really appreciate the feedback.

 

[2001LC]

Were not driving 80k lb. tractor trailers, most of rigs are more than capable of relying on the brakes is all I'm saying. Of course there is a time and a place to use your gears and overdrive to help slow your rig down but my point is although it is proper technique to do so, it's not a necessity under most conditions and shouldn't have anything to do with the current problem in question.

Sorry but I cant empsizes enough. Do NOT use brakes to control downhill speed. Doing so you risk your life! Loss of braking or fire can kill.

We do not know at this point, that overheating didn't have anything to do with OP issue. He implied he did not engine brake on downhill. So brakes were likely very hot. If indeed rear was his issue, as he thinks. The heat may have transferred from disk to E-brake drums. He may have had e-brake on. E-brake grabbing is not common but happens, and may or may not kick on ABS. Again he said no dash lights or alams (beeps).

OP also asked if he should learn how to better control speed "downhill shifting" So not sure why you'd say "and shouldn't have anything to do with the current problem in question.." OP is asking more than one question! And riding brakes is a problem!

I would have said "OP case is likely loose front end, which most are when brake grab suddenly." i.e wheel bearings, TRE, ball joints, steering rack setting off ABS. Which in those cases, ABS kicks in on the turns. Which also lights up dash and alarm. He said he did not have either lights or beeps. So over heating is something that needs considering. At least once he verifies ABS light & alarm are working properly and E-brake shoe retainers not damaged.

BTW:
It is never appropriate to use brakes to control downhill speed, no matter of weight. I've see everything from big rigs to VW bugs smoking or on fire from doing so.

Here a set of cooked rotors I pulled last month, from a TX rig. Which TX, doesn't have many long descents that I know of.
Pictures doesn't show how black they really are. Driver complain his newish aftermarket rotors already wrapped. They were wrap the day china spit them out of a factory. It's overheating from riding brakes on downhill, that revealed the wrapage (run out out of spec)

Again hard to see in picture. These pads from CO driven rig (Driver from flat land or rather hilly TN). They're are melting. In a less than 3 ton rig (05LC)

Also cooked his caliper piston boots. Any guess as to what seal looks like!

 

[AlpineAccess]

Dropping OD does enough engine braking for my 99 on nearly all of our passes here. For any overrun speed on descents I will use my brakes for 5-10 seconds and then let off to cool down, then apply again until engine braking is doing enough again.

That being said, the sections where I do regularly hold a gear lower are The Ike to Dillon and CD to Vail. If I'm towing then yes, I hold a gear down and sit in the climb lanes with the semis to let my brakes and trans stay cool. It's not a race.


I am on the same rotors and pads from 2018 with no adverse effects. Don't ride the brakes and take time to cool down the vehicle/trailer brakes (and trans) when you're towing.

I've never heard of or experienced the issue you are having.

 

[2001LC]

I can descend any pass in The Rocky Mountains either side of Great Divide, without touching brakes. With two exception: Sudden slowing needing for road hassard! OR Speed to high (poor planning on my part) for transmission to drop down a gear.

I learned to drive in a rear wheel drive, 4 spd manual stick shift, without ABS or disk brakes (drum brake & shoes). Those, driving stick shift (manual transmission) are accustomed to engine braking. But so many think with an automatic transmission, they need to brake to control speed. They either don't know automatic transmission can engine brake or they fear damaging the transmission. Transmission are design to engine brake, and it will not damage a health transmission.

Next time on a decent, try it. See if you can descend a long mountain pass, without ever touching the brakes, and hold speed limit. You'll find once you get the hang of it, it's much more relaxing, comfortable and gives better control. Save your brake for stopping!

You can spot flatland or true Colorado Natives, by brake lights or lack thereof on the passes...LOL

 

[awesomeissquid]

I can descend any pass in The Rocky Mountains either side of Great Divide, without touching brakes. With two exception: Sudden slowing needing for road hassard! OR Speed to high (poor planning on my part) for transmission to drop down a gear.

I learned to drive in a rear wheel drive, 4 spd manual stick shift, without ABS or disk brakes (drum brake & shoes). Those, driving stick shift (manual transmission) are accustomed to engine braking. But so many think with an automatic transmission, they need to brake to control speed. They either don't know automatic transmission can engine brake or they fear damaging the transmission. Transmission are design to engine brake, and it will not damage a health transmission.

Next time on a decent, try it. See if you can descend a long mountain pass, without ever touching the brakes, and hold speed limit. You'll find once you get the hang of it, it's much more relaxing, comfortable and gives better control. Save your brake for stopping!

You can spot flatland or true Colorado Natives, by brake lights or lack thereof on the passes...LOL

Can you share a how to for using engine braking in our 100s?

 

[Tanner H]

@awesomeissquid I usually turn my o/d off . that helps a bit. not full on engine braking but helps keep me foot off the brake pedal less on mountain descents. I'm no local though so I'm still on the brakes way too much. meanwhile there is a 79 year old lady behind me in a 93 outback riding my ass. You can def point out the locals.

 

[2001LC]

Those flatlanders that ride my ass in the mountains, are usually sorry. As they have trouble maintaining control. I did have I a few weeks ago on a suspension completion test run. Guy stayed on my ass up Berthoud pass, not easy when I'm pushing it for the 500thr'd or so time over the divide. I final braked a slowed so he'd pass, in his sport cars. He was a local just bird dogging me for smokeys. I must admit, I sometimes do the same when I see a speeder.

Engine braking:
Just shift down transmission gears.

98-02 have overdrive button on shifter, press OD (OFF) and you see RPMs come up. That's where we first start slowing (engine braking). If you need to reduce speed more, drop transmission to "2". than "L" if needed. To really granny it down, stop and shift transfer case to "LOW".

In 03-07, OD off is when we move shift from "D" to the left, than "3", "2" or "1/L"

The owner's manual has each gears MPH range listed. If we shift lower than that gears range allows for. Transmission will not shift down, until MPH speed reduced. In those cases, often we must slow by braking until MPH mesh with transmission gear selected. At the point MPH slows enough for the transmission to engage the lower gear you've selected. You'll be lunged forward, like sudden braking. You'll see RPMs jump to near redline as this happens. This is from not planning ahead or emergency slowing. Which is find, as long as not in a high speed turn or on slippery/ice roads

Be warned, in turns, on ice or slippery condition. This sudden braking of transmission as speed drops and lower gear engages, can cause vehicle to skid in turn or on ice/slippery condition. It's all about proper planning ahead. In high speed turns/curves slow before turn. On icy condition, we do not want any moves, like sudden engine braking nore acceleration or heavy steering. So we must easy into gears at lower MPH, accelerate gently and turn easy (wide and slow)

I've a story posted somewhere in mud. How just back off accelerator pedal or touching it would put my 240Z into a slip. More than 30 to 40 vehicles in front of me, began spinning out of control on icy HWY I-70 eastbound out of Eisenhower tunnel. You could see vehicle after vehicle brake lights tap on, than they spun out of control. Not one vehicle in front of me made it through. Even just letting off gas pedal and they'd spin. Only about halve the vehicles following me, made it through the mass of spinning vehicles. IT WAS SO INTENSE!. Key was constant speed, and very light steering too lightly ver around on straightest line possible. No sudden moves!

Practice on dry condition first. Get the hang of it, before winter. Learn to plan ahead, so no need to touch brakes, or feel any forward lung as lower gear takes hold.

Me, I drive with right hand on the shifter most all the time. It's second nature to me, like driving a stick. I shift very often. Sometime in emergency braking, I'll shift down to slow faster.

Practice makes perfect.

 

[awesomeissquid]

Those flatlanders that ride my ass in the mountains, are usually sorry. As they have trouble maintaining control. I did have I a few weeks ago on a suspension completion test run. Guy stayed on my ass up Berthoud pass, not easy when I'm pushing it for the 500thr'd or so time over the divide. I final braked a slowed so he'd pass, in his sport cars. He was a local just bird dogging me for smokeys. I must admit, I sometimes do the same when I see a speeder.

Engine braking:
Just shift down transmission gears.

98-02 have overdrive button on shifter, press OD (OFF) and you see RPMs come up. That's where we first start slowing (engine braking). If you need to reduce speed more, drop transmission to "2". than "L" if needed. To really granny it down, stop and shift transfer case to "LOW".

In 03-07, OD off is when we move shift from "D" to the left, than "3", "2" or "1/L"

The owner's manual has each gears MPH range listed. If we shift lower than that gears range allows for. Transmission will not shift down, until MPH speed reduced. In those cases, often we must slow by braking until MPH mesh with transmission gear selected. At the point MPH slows enough for the transmission to engage the lower gear you've selected. You'll be lunged forward, like sudden braking. You'll see RPMs jump to near redline as this happens. This is from not planning ahead or emergency slowing. Which is find, as long as not in a high speed turn or on slippery/ice roads

Be warned, in turns, on ice or slippery condition. This sudden braking of transmission as speed drops and lower gear engages, can cause vehicle to skid in turn or on ice/slippery condition. It's all about proper planning ahead. In high speed turns/curves slow before turn. On icy condition, we do not want any moves, like sudden engine braking nore acceleration or heavy steering. So we must easy into gears at lower MPH, accelerate gently and turn easy (wide and slow)

I've a story posted somewhere in mud. How just back off accelerator pedal or touching it would put my 240Z into a slip. More than 30 to 40 vehicles in front of me, began spinning out of control on icy HWY I-70 eastbound out of Eisenhower tunnel. You could see vehicle after vehicle brake lights tap on, than they spun out of control. Not one vehicle in front of me made it through. Even just letting off gas pedal and they'd spin. Only about halve the vehicles following me, made it through the mass of spinning vehicles. IT WAS SO INTENSE!. Key was constant speed, and very light steering too lightly ver around on straightest line possible. No sudden moves!

Practice on dry condition first. Get the hang of it, before winter. Learn to plan ahead, so no need to touch brakes, or feel any forward lung as lower gear takes hold.

Me, I drive with right hand on the shifter most all the time. It's second nature to me, like driving a stick. I shift very often. Sometime in emergency braking, I'll shift down to slow faster.

Practice makes perfect.

Thank you for explaining that! I have experienced the lunge forward with downshifting and it can be a bit scary if you are not expecting it. If you are already within the gear MPH range is the lunge less intense?

 

[SHIfTHEAD]

Were not driving 80k lb. tractor trailers, most of rigs are more than capable of relying on the brakes is all I'm saying. Of course there is a time and a place to use your gears and overdrive to help slow your rig down but my point is although it is proper technique to do so, it's not a necessity under most conditions and shouldn't have anything to do with the current problem in question.

Very true, but also don't have brakes (and therefore their mass) for 80K tractor trailers either. If we did then we probably could ride the brakes to the bottom. It's really just about heat dissipation, not braking system performance. The systems are designed for short duration usage with enough time to cool the brakes, and just as importantly, the brake fluid down. Because even if the pads don't lose their effectiveness from the heat you can still boil the brake fluid and make the system non-functional.

 

[AlpineAccess]

Thank you for explaining that! I have experienced the lunge forward with downshifting and it can be a bit scary if you are not expecting it. If you are already within the gear MPH range is the lunge less intense?

Yes, if trailering down a grade it is easiest to get on the brakes and reduce speed 10mph or so then downshift and let engine braking hold your speeds down. I have never gone to L while in high range. Maybe if you're max towing and you don't have trailer brakes I could see someone doing this, but you'd be crawling and I'd be more curious about what my transmission temps were doing than my brakes. Even when downshifted, I don't let my revs run way up and have no problem using my brakes to peel some speed off when I start moving quickly.

I bet put up against another 100 series with a similar load out who isn't using engine braking, you'd be doing at least 25% less braking just with OD off and stepping down a gear you'll be doing more than 50% less braking. That being said, these aren't big high torque motors or diesels with a lot of back pressure to significantly reduce speed, so I just do whatever feels comfortable.

If you're towing in the Rockies (at least in CO or WY) with surge brakes, its a good idea to use pull offs to cool your trailer brakes regularly - or you might be setting yourself up for a bad day. Even with my electric brakes, if I can't give them a long up-hill to cool off on after a braking event I will pull off to check the hubs. I keep fresh grease in my trailer hubs, but we don't always tow our own trailers and I want to make sure I'm not cooking the grease and about to blow up a hub in someone else's trailer.

When off road it's really common for my t-case to be in low range and L for "offroad cruise control", engine braking down hill and my foot on the brake providing light pressure for entire sections of trail. Offroad, two-foot driving or "off road cruise control" in areas where there are large rocks, undulations, drop offs, is taught a lot in 4x4 courses and is commonly used. Holding the throttle up slightly and using the brake pedal to restrain forward movement and control slippage protects gearing, especially in the diffs, from shock loading.