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Discussion Starter #1
Looking for suggestions on the proper way to pull a grade in my 06 LBZ. The family and I will be heading up Monarch Pass in Colorado this summer and I've never pulled on roads like this before. We will be pulling a 22' enclosed trailer loaded with side by sides. Truck is a all stock 2006 LBZ. Do you just leave it in drive and let the tranny do its thing or should I be using manual mode and keeping it in a low gear?

Any suggestions would help. Thanks!
 

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T/H on and shift in manual mode. You might hold 5th for a little while but i would shift into 4th. If the truck gets too hot turn the heat on full blast. I assume you have no gauges but your oil temps will be hot by the end of the run.
 

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You really should have an EGT gauage, overheating your turbo is no fun from
what I hear. I always guage my rpms and gearing using my egt readings.
 
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Sorry not much help on an 06, but I just put mine in T/H set cruse at 40 (it goes +/- 5 MPH), and set the exhaust brake, then I just keep my camper between the lines. I'm hauling around 21K.

On an older diesel set T/H use manual (in what ever gear you needed to go uphill and maintain speed or one lower) going down hill let the engine trans do the work and try to stay off the brakes as much as possible, don't exceed 40-45 mph on the downgrade, and watch your temps.

Also don't worry about the folks behind you they fly up and down that pass all the time, they will go around when allowed, your safety is first.
 
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You need to keep your RPM's up. Should be at about 2400 RPM (or more) while pulling up these long grades. Let the engine do the work - don't lug it. This will allow more cooling (if needed), will turn your fuel pump faster (reduce tendency for P0076), allow transmission to work in a more efficient band. Probably other benefits also. Your truck will definitely do the job so don't be afraid of going there. My 5th wheel is about 10,500 lbs and have had no problems going over Eisenhower Summit which has just about the same altitude. Don't know comparison on the grade however.
 

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Discussion Starter #6
To answer, no I do not have any aftermarket gauges. With me not having any sort of tune or programmer I just never thought I'd need something like that with it being all stock. Other than keeping an eye on rpm's and making sure I'm not dogging the motor what else to watch for
 

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These trucks really should come stock with a EGT gauge but since they don't and you don't have one just take your time and go slow both up the pass and slow going down the other side too. I use the T/H mode in auto.
 

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Discussion Starter #8
And I should let the tranny do the breaking down grade instead of brakes correct? What should I keep my decent RPM's around?

Thanks again for all the help guys, much appreciated
 

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Like said use the T/H whenever towing. Anticipate the fan kicking on. If you've never heard it before, the roar may scare you at first. Do not try to keep up with passenger cars or folks not towing. Leave plenty of room between you and the cars in front of you to avoid panic stops. Stay within your comfort zone. If you start getting hot any you have the A/C on, turn off the A/C.

On a stock truck it will limp before anything would break.
 

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I was just in Colorado about 6 weeks ago. Talked to some campers from Louisiana (called themselves "flat landers") and the wife complained about lots of smell coming down Wolf Creek Pass. I pointed out that I use my brakes very little, but that means going slow and using lower gears. They seemed concerned about the automatic transmission and I pointed out it's fine to use it, and SHOULD be used for braking. (They weren't even towing, but I'm also not sure what kind of truck they had.)

To re-iterate what some others have suggested:
1) Uphill: Keep in T/H, slow down as needed, keep the RPMs in the low 2000's (say 2000-2400), watch engine temp and oil pressure (you can get another clue to internal temps if the oil pressure drops). Personally, I like about 3/4 throttle for a long climb and might select a gear to keep it from upshifting.
2) Downhill: Keep in T/H, slow down (45 is often good, but faster/slower may be needed at times), you should be able to find a way to use the brakes without overusing them, drop to a lower gear. ~3000 rpm would not be unusual.
 

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Just FYI

Just in case anyone wanted to know about Colorado.
Maximum Grades on Colorado Mountain Passes
Listed in descending elevation.
Name
Highway
Elevation
Maximum Grade
Independence open seasonally
SH 82
12,095’
6%
Loveland
U.S. 6
11,992’
6%
Hoosier
SH 9
11,541’
8% N
Slumgullion
SH 149
11,361’
9.4% N; 7.9% S
Fremont
SH 91
11,318’
5.7%
Berthoud
U.S. 40
11,315’
6.1% N; 6% S
Monarch
U.S. 50
11,312’
6.4%
Eisenhower Tunnels Approaches
I-70
11,158’
6% W
Red Mountain
U.S. 550
11,018’
7%+
Molas
U.S. 550
10,910’
7% +
Spring Creek
SH 149
10,901’
7.5%
Wolf Creek
U.S. 160
10,850’
6.8%
Vail
I-70
10,666’
7%
Coal Bank
U.S. 550
10,640’
6.5%
Tennessee
U.S. 24
10,424’
6%
Cameron
SH 14
10,276’
3.8% E
La Manga
SH 17
10,230’
5.2%
Lizard Head
SH 145
10,222’
4.1%
North/North Cochetopa
SH 114
10,149’
6%
Cumbres
SH 17
10,022’
6.3%
Kenosha
U.S. 285
10,001’
5.3% E
Red Hill
U.S. 285
9,993’
6%
Cucharas
SH 12
9,941’
5.9% N; 5.4% S
Squaw
SH 103
9,807’
6%
Willow Creek
SH 125
9,621’
6.3%
Gore
SH 134
9,527’
6.3%
Wilkerson
U.S. 24
9,507’
5.8%
Rabbit Ears
U.S. 40
9,426’
6.8% N
La Veta/North La Veta
U.S. 160
9,413’
6%
Trout Creek
U.S. 24/285
9,346’
5.2%
Ute
U.S. 24
9,165’
5.6% E
Poncha
U.S. 285
9,010’
3%
Dallas Divide
SH 62
8,970’
6.4% E; 5% W
Muddy
U.S. 40
8,772’
5.6%
McClure
SH 133
8,755’
8%
Douglas
SH 139
8,268’
7%
Raton
I-25
7,834’
6%

SH 5 to Mt. Evans, which reaches an elevation of 14,150’, is not considered a mountain pass. Maximum is grade 9% to Summit Lake; 15% beyond Summit Lake. This is the highest paved road in North America and is open seasonally.
Milner Pass (10,758’) and Trail Ridge High Point (12,183’) are on U.S. 34 in Rocky Mt. National Park but are not maintained by CDOT. Maximum grade on both is 5.4%. Open seasonally.
 

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put it in T/H and Drive it its all stock no thing to worry about. These trucks are dummy proof in stock mode

X2.

I put my stock 05 LLY in T/H,Drive and let the Allison do the job it was designed to do.

Never have had a problem with engine lugging when in T/H.

Down grades leave it in T/H,Drive and brake firmly to the speed you want to go down the grade. Thn Allison will do the rest.

You may have to brake before some of the sharper curves but for the most part the Allison will provide enough grade braking.

I have an EGT gauge and if I use T/H I do not have EGT temperature problems.
 

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we tow over lots of steep grades with about a 10,000 trailer. with the 04.5 I put it in TH and lock out overdrive on the uphill climbs. I've found that unless it is a very steep and long grade (8% or greater), TH will let the engine hunt between 4th and 5th. with a 6 speed, i'd lock it in 4th. I usually run around 50-55, since steep grades I'm on also have significant curves, and 50ish is a speed I can maintain comfortably on most curves. Otherwise it's speed up on the straight, then back off for the corner and repeat. not good for economy.

When the fan comes on (not if but when) you will know it!!! don't worry, just watch temps and water below 230 or so, you'll be ok.

On the downhill take it out of overdrive lockout leave it in TH and use the grade brake. don't worry when it goes down to 2nd gear and 5,000rpm. fuel is shutoff, your using engine friction and turbo backpressure to slow down. On the later years, like my 2015, I just set the cruise control on downhill, turn on the exhaust brake and it will hold speed downhill as well.

Only time service brakes should get used much at all is on a very very steep (10+% grade) and very curvy downhill with 20mph or lower turns.

A recent test of towing max rated load up and through the esinhower tunnel and down with the chevy, ford, dodge diesels was done. . the 2015 duramax pulled the whole grade up at 50 or 55mph using TH and cruise control and kept 50 mph on the downhill side without ever touching the service brakes, just using cruise control and turning on the exhaust brake.

BTW, the ford and dodge performed similarly,

Remember, a diesel really doesn't have any "compression braking" (really vacuum breaking) since the engine is unthrottled, that's why the grade brake and exhaust brake are their. Engine frictional losses are a cubic function of rpm. double the rpm and frictional losses go up 8 times!! so, letting the engine turn close to 5,000rpm with no fuel has 8 times the frictional losses to slow you down compared to 2500rpm.

and at that rpm, the turbo with the vanes properly positioned for max backpressure can add lots more retarding horsepower.
 

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i'd think with a 6speed, you could lug it under 2000rpm and not worry about hurting the trans as much as a 5 speed (been there, done that).from what i've seen, the egt creep isn't as bad as people make it out to be. you're not gonna torch a motor with it all stock. i would set the cruise and let the truck work it out. thats what i have been doing for 130,000 (260k total) miles and the trailers have only gotten heavier and larger.
 

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i'd think with a 6speed, you could lug it under 2000rpm and not worry about hurting the trans as much as a 5 speed (been there, done that).from what i've seen, the egt creep isn't as bad as people make it out to be. you're not gonna torch a motor with it all stock. i would set the cruise and let the truck work it out. thats what i have been doing for 130,000 (260k total) miles and the trailers have only gotten heavier and larger.
5 and 6 speed have EXACTLY the same first through 5th gears, 6 speed just adds a second overdrive.

Long steep hills need more than 2000 rpm to keep up the speed with a heavy load.

but as you say, put it in TH and let the truck work it out.
 

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If in doubt, slow down and keep your RPM's high. It'll eat more fuel, but it will cool things down. Especially the EGT's.
 

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5 and 6 speed have EXACTLY the same first through 5th gears, 6 speed just adds a second overdrive.

Long steep hills need more than 2000 rpm to keep up the speed with a heavy load.

but as you say, put it in TH and let the truck work it out.
i was referring more to the line pressure and clutch pressure of c2 and c3 in the 5 speed vs the 6 speed. you'll limp a 5 speed lugging it in 5th before you will a 6 speed in 5th.
 

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Lots of good info in above posts.
Pulling, put in T/H, in drive, and then drive it. If it warms over 220 or so, manually drop a gear, and run it 2000 to 2400 RPM. Watch the tach more than the speedo. I find running over 2500 RPM creates too much heat from internal friction. Much under 1900 doesn't have enough circulation/air flow for cooling.
If you do have to stop on a grade, then when you restart, stand on it to get the speed over 25 MPH, let off throttle so it shifts into second then easy back into it. That will get the convertor locked which saves your transmission from heating as much.

Now for going down. Still in T/H, in drive. Snub the brakes as the speed increases. It will down shift and start retarding. If still too fast /gaining speed, snub the brakes hard twice again. If under 3500 RPM it should step down another gear, and retard harder. The retarding/grade brake is unbelievable when the RPM is over 4000 RPM.

THE IDEA IS TO HAVE COLD BRAKES WHEN YOU HIT THE BOTTOM. Drive it more like a semi driver drives his unit. It will be more fun in the long run. You don't have to win the race.... just arrive alive.

Dropping into Denver east bound on I-70, I use the throttle once near the "NOT THERE YET" sign. Otherwise grade braking, very little service brakes, and land in Denver, happy.
 

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I live in colordao, i drive these passes all the time. I have a 5k trialer... with a 8k tractor....
you will have no problem... just be easy.... as stated dont try to win the race.
make sure your hoses and belts are in good condition, radiator, coolant levels are topped off, and go.... these are not that hard of climbs. Some of the side roads... can be steep, and cause problems. just make sure your fluids are full,and be a little easier if its the heat of the day.
 
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