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Discussion Starter #1
Towing my toy hauler with a 900lbs Victory Vision in the back and camping gear, food ect ect
My wife and myself. Two big dogs and a full load of dog pens and other junk.
BBQ ect ect
Back of the truck was full.
Here is the killer that I don’t understand. I bought a tongue scale. And with this trailer empty the tongue wt shows 800lbs .
Seems when they build these travel trailers they place the axles to far back. Witch places a lot of weight on the truck.
Then with all the storage located at the front of the trailer these even more weight on the truck.

I used the electric jack to lift the trailer and the truck before setting the weight distribution hitch....
I also have 2 friction type anti sway bars. That seem to do nothing for sway no matter how tight I run them.
Also I have tried everything from to much weight on the back to to much on the front and it still wanders constantly.

I absolutely hate the transmission downshifting when you apply the brakes, it does nothing but rev the **** out of the motor. So I run it in manual mode set in 5th with tow haul on. This allows the transmission to do its thing but not down shift when the brake is applied.
For the most part the little 2.8 pulls really well. At times it would down shift going up hills to 4th and rev around 3k.
Today I was trying to make up time and downshifts to 4th would rev to 3.5k. This was when I was running 120kph. Approx 75mph
Funny that at the higher speeds the trailer pulled without any sway or wandering.

Had my first issue today.
Stopped to get diesel and I don’t know who the ass holes are that designs the fuel stations these days but they didn’t think about people pulling a trailer. As when you pull up to the pump you are pointing at the station. And there is no way you can pull through as there is not enough room to make the turn.
And they are busy. So you can’t back up. WTF..........Idiots.

So I make the turn but the trailer connector gets jammed between the anti sway bar and the a frame.
This locks the brakes on the trailer and it will not move.
I figure the break away switch fked up. I rip the wires out of it. Still no move.
So I drag it around the corner out of the way. Find the crushed section of wire and fix it.
Back on the road but no break away any more.

So the real reason I am posting here is because I have herd so muck about transmission temps.
I have the Bluetooth dongle and software so I can monitor turbo boost EGR temps ect ect.
I had the trans temp showing on the display between the speedo and the tach.
And I had my iPad setup to show motor oil temp and water temp, boost ect.
The highest I seen the transmission temp was 233f average was 210 - 220.
It was the motor oil temp that surprised me. 245f It would spike up very fast when the transmission would downshift to 4th and climbing up hills.
The only thing I could think about was the piston jets cooling the underside of the pistons when the truck was really working hard.
Water temp would run around 210 during long up hill runs.
I should mention I run with cruise control on. So the truck doesn’t get to slow down on the hills.

How many of you let the truck run over 3k RPM for long periods of time when pulling heavy trailer?
Especially with a head wind.
I felt I was killing it but after passing a bunch of traffic I didn’t want them passing me back on every hill.
 

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So, the transmission downshifting on the truck. It does get a little aggressive at times. But your statement about "all it does is rev the **** out of the motor" is incorrect. When you have tow-haul on, in redoes the shift points to allow for more power while accelerating and hopefully less down-shifting to get up to speed because it shifted too early the first time. It also holds gears to hopefully cut down on using your brakes and heating them up. The main thing is that tow-haul turns on turbo braking. And that doesn't work at all at lower RPM's because there isn't enough pressure being built. So, if you aren't stopping fast enough, it downshifts again to create more RPM's and pressure and to slow you down faster. Usually once you press on the accelerator again, it will come out of it.

I don't like that it gets carried away sometimes as well, so I usually turn tow-haul on to activate the turbo braking, and then shift to manual so I still have that feature, but I can control when it downshifts. Also, tow-haul while in Drive limits the truck to 5th gear I believe (I've never made it to 6th while in drive with it activated).

The higher transmission temps are supposedly okay when towing. As in, 235 and below is acceptable is the general consensus. Older transmissions, you started getting worried at those temps. If it's a worry to you, you may consider changing your transmission fluid, especially if you tow a lot. I would like to think my trans runs cooler even unloaded and not towing, than other people have claimed, since I changed out to AMSOIL OE Fuel-Efficient fluid.

For the engine temp though, the gauge on your dash has been proven to be a dummy gauge that tells you that the truck is up to temperature, or over-temperature (should that happen). My truck runs around 200 I believe most days (unloaded, not pulling). So, 210 isn't bad at all. But back to the dummy gauge. Whenever I hook up my Auto-Cal which is my tuning tool, which can also monitor and record any sensor connected to the truck, it states that when my truck is at operating temp on the dash (200), it is in reality at around 175 on the auto-cal. Which, many others with auto-cal or OBD readers have confirmed this also. Unless that 210 that you stated was recorded from the OBD dongle and not your dash gauge, in which case, it's probably accurate. I mean, going up a long hill with something heavy and not the most aerodynamic, it makes sense that it would heat up. 210 is still safe.
 

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Discussion Starter #3
So, the transmission downshifting on the truck. It does get a little aggressive at times. But your statement about "all it does is rev the **** out of the motor" is incorrect. When you have tow-haul on, in redoes the shift points to allow for more power while accelerating and hopefully less down-shifting to get up to speed because it shifted too early the first time. It also holds gears to hopefully cut down on using your brakes and heating them up. The main thing is that tow-haul turns on turbo braking. And that doesn't work at all at lower RPM's because there isn't enough pressure being built. So, if you aren't stopping fast enough, it downshifts again to create more RPM's and pressure and to slow you down faster. Usually once you press on the accelerator again, it will come out of it.

I don't like that it gets carried away sometimes as well, so I usually turn tow-haul on to activate the turbo braking, and then shift to manual so I still have that feature, but I can control when it downshifts. Also, tow-haul while in Drive limits the truck to 5th gear I believe (I've never made it to 6th while in drive with it activated).

The higher transmission temps are supposedly okay when towing. As in, 235 and below is acceptable is the general consensus. Older transmissions, you started getting worried at those temps. If it's a worry to you, you may consider changing your transmission fluid, especially if you tow a lot. I would like to think my trans runs cooler even unloaded and not towing, than other people have claimed, since I changed out to AMSOIL OE Fuel-Efficient fluid.

For the engine temp though, the gauge on your dash has been proven to be a dummy gauge that tells you that the truck is up to temperature, or over-temperature (should that happen). My truck runs around 200 I believe most days (unloaded, not pulling). So, 210 isn't bad at all. But back to the dummy gauge. Whenever I hook up my Auto-Cal which is my tuning tool, which can also monitor and record any sensor connected to the truck, it states that when my truck is at operating temp on the dash (200), it is in reality at around 175 on the auto-cal. Which, many others with auto-cal or OBD readers have confirmed this also. Unless that 210 that you stated was recorded from the OBD dongle and not your dash gauge, in which case, it's probably accurate. I mean, going up a long hill with something heavy and not the most aerodynamic, it makes sense that it would heat up. 210 is still safe.
Your missing everything I said.....
I was in tow haul mode.
The down shifting is very aggressive and does nothing on my truck but rev the shhit out of the motor.
It doesn’t help in any way to slow my truck. Never has.
Because I don’t believe reving in the 4K region is good for these motors I use manual mode so it doesn’t do that stupid down shifting..... brakes are cheep these motors are expensive. And the trailer has brakes too so why would I want to rev a diesel that high. The wear on the motor must be massive reving like that.

Today for the first time ever while in tow haul mode the truck started to shift info 6th gear.
Never seen it go to 6th with tow haul on before. There was a lot of steep hills and the transmission was dropping to 4th and reving to 3500 rpm for long periods of time climbing the hill. Then once the hill was crested it would go from 4th to 6th and the rpm would drop to below 2k
Didn’t stay in 6th long with 6k and a head wind.

Also
Didn’t have high transmission temps.
I had high motor oil temps 245 deg
Yes for some reason GM put a fake water temp gauge on the truck
But
I was looking at my iPad for the water temp not the dic
I had the dic displaying the transmission temp.

I also seen EGR temps of 1100 deg....

Personally I think GM should SCRAP this 2.8 and put the new inline 6 cyl 3.0 litre in these trucks .
I don’t trust this 4 banger

Pulling my trailer on flat ground took 300 ftLbs of torque and around 150 hp. That’s to close to max output for longevity.....
 

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Towing my toy hauler with a 900lbs Victory Vision in the back and camping gear, food ect ect
My wife and myself. Two big dogs and a full load of dog pens and other junk.
BBQ ect ect
Back of the truck was full.
Here is the killer that I don’t understand. I bought a tongue scale. And with this trailer empty the tongue wt shows 800lbs .
Seems when they build these travel trailers they place the axles to far back. Witch places a lot of weight on the truck.
Then with all the storage located at the front of the trailer these even more weight on the truck.

I used the electric jack to lift the trailer and the truck before setting the weight distribution hitch....
I also have 2 friction type anti sway bars. That seem to do nothing for sway no matter how tight I run them.
Also I have tried everything from to much weight on the back to to much on the front and it still wanders constantly.

I absolutely hate the transmission downshifting when you apply the brakes, it does nothing but rev the **** out of the motor. So I run it in manual mode set in 5th with tow haul on. This allows the transmission to do its thing but not down shift when the brake is applied.
For the most part the little 2.8 pulls really well. At times it would down shift going up hills to 4th and rev around 3k.
Today I was trying to make up time and downshifts to 4th would rev to 3.5k. This was when I was running 120kph. Approx 75mph
Funny that at the higher speeds the trailer pulled without any sway or wandering.

Had my first issue today.
Stopped to get diesel and I don’t know who the ass holes are that designs the fuel stations these days but they didn’t think about people pulling a trailer. As when you pull up to the pump you are pointing at the station. And there is no way you can pull through as there is not enough room to make the turn.
And they are busy. So you can’t back up. WTF..........Idiots.

So I make the turn but the trailer connector gets jammed between the anti sway bar and the a frame.
This locks the brakes on the trailer and it will not move.
I figure the break away switch fked up. I rip the wires out of it. Still no move.
So I drag it around the corner out of the way. Find the crushed section of wire and fix it.
Back on the road but no break away any more.

So the real reason I am posting here is because I have herd so muck about transmission temps.
I have the Bluetooth dongle and software so I can monitor turbo boost EGR temps ect ect.
I had the trans temp showing on the display between the speedo and the tach.
And I had my iPad setup to show motor oil temp and water temp, boost ect.
The highest I seen the transmission temp was 233f average was 210 - 220.
It was the motor oil temp that surprised me. 245f It would spike up very fast when the transmission would downshift to 4th and climbing up hills.
The only thing I could think about was the piston jets cooling the underside of the pistons when the truck was really working hard.
Water temp would run around 210 during long up hill runs.
I should mention I run with cruise control on. So the truck doesn’t get to slow down on the hills.

How many of you let the truck run over 3k RPM for long periods of time when pulling heavy trailer?
Especially with a head wind.
I felt I was killing it but after passing a bunch of traffic I didn’t want them passing me back on every hill.
When you have the opportunity try using the truck stops and pull into the big truck lanes. Use them but be careful the pumps are high volume pumps and will fill your tank in about 20 seconds.
 

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Towing my toy hauler with a 900lbs Victory Vision in the back and camping gear, food ect ect
My wife and myself. Two big dogs and a full load of dog pens and other junk.
BBQ ect ect
Back of the truck was full.
Here is the killer that I don’t understand. I bought a tongue scale. And with this trailer empty the tongue wt shows 800lbs .
Seems when they build these travel trailers they place the axles to far back. Witch places a lot of weight on the truck.
Then with all the storage located at the front of the trailer these even more weight on the truck.

I used the electric jack to lift the trailer and the truck before setting the weight distribution hitch....
I also have 2 friction type anti sway bars. That seem to do nothing for sway no matter how tight I run them.
Also I have tried everything from to much weight on the back to to much on the front and it still wanders constantly.

I absolutely hate the transmission downshifting when you apply the brakes, it does nothing but rev the **** out of the motor. So I run it in manual mode set in 5th with tow haul on. This allows the transmission to do its thing but not down shift when the brake is applied.
For the most part the little 2.8 pulls really well. At times it would down shift going up hills to 4th and rev around 3k.
Today I was trying to make up time and downshifts to 4th would rev to 3.5k. This was when I was running 120kph. Approx 75mph
Funny that at the higher speeds the trailer pulled without any sway or wandering.

Had my first issue today.
Stopped to get diesel and I don’t know who the ass holes are that designs the fuel stations these days but they didn’t think about people pulling a trailer. As when you pull up to the pump you are pointing at the station. And there is no way you can pull through as there is not enough room to make the turn.
And they are busy. So you can’t back up. WTF..........Idiots.

So I make the turn but the trailer connector gets jammed between the anti sway bar and the a frame.
This locks the brakes on the trailer and it will not move.
I figure the break away switch fked up. I rip the wires out of it. Still no move.
So I drag it around the corner out of the way. Find the crushed section of wire and fix it.
Back on the road but no break away any more.

So the real reason I am posting here is because I have herd so muck about transmission temps.
I have the Bluetooth dongle and software so I can monitor turbo boost EGR temps ect ect.
I had the trans temp showing on the display between the speedo and the tach.
And I had my iPad setup to show motor oil temp and water temp, boost ect.
The highest I seen the transmission temp was 233f average was 210 - 220.
It was the motor oil temp that surprised me. 245f It would spike up very fast when the transmission would downshift to 4th and climbing up hills.
The only thing I could think about was the piston jets cooling the underside of the pistons when the truck was really working hard.
Water temp would run around 210 during long up hill runs.
I should mention I run with cruise control on. So the truck doesn’t get to slow down on the hills.

How many of you let the truck run over 3k RPM for long periods of time when pulling heavy trailer?
Especially with a head wind.
I felt I was killing it but after passing a bunch of traffic I didn’t want them passing me back on every hill.
Please stop towing until you have sorted out your dangerous set up AND operation. You "wander constantly", your anti sway bars "seem to do nothing for sway" your engine braking seems ineffective (first time I have seen this complaint, and mine is fine with a "heavy" tow), your average trans temp range is much higher than it should be, and your engine runs hot (also first for me to read about). All probably linked to a bad set up, made worse by your tow speed.

I could flow chart how to regain safety, but you seem knowledgeable and know what to do. However, feel free to provide all loaded axle weights to be used with the hitch weight you already provided. I'll guarantee lots of help from this forum.

If you must tow this trailer, at 75 m/h, with the bed/cab load you described, then you either have the right truck (meaning pushing but not exceeding GVWR, less than 80% of GCVWR, and proper weight distribution), or you don't. If not, then check up, starting with the F150 diesel, then the Nissan 5.0 Cummins, and so on, until you are again safe and running your rig to last. Of course, I'll defer to those with specific vehicle criticisms, as I don't track them in fora, and haven't used them. Lastly, I benefit from not needing/wanting to go faster than 61-62 m/h, while towing my 21' Escape 5.0 TA bed hitch, with a loaded cab, filling the remaining bed volume, and a trailer with food, water, e bikes on back, other stuff. It's a whole different tow at 75, and if I was bound to go that fast I would have made a different tractor choice.

Not going to check again, but doesn't the new GMC 3.0 diesel feature lots of aluminum? If so, big down thumb from me. Yes, the aero diesels might be partly/mostly aluminum (and yes, they DO make them, for geographies without Av Gas access), and vehicles like my old BMW 650 Dakar had a converted aero engine. But airplane diesel conversions push 6 figures, so I'm guessing that a reliable aluminum truck diesel would almost double it's current price.
 

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Discussion Starter #6
Please stop towing until you have sorted out your dangerous set up AND operation. You "wander constantly", your anti sway bars "seem to do nothing for sway" your engine braking seems ineffective (first time I have seen this complaint, and mine is fine with a "heavy" tow), your average trans temp range is much higher than it should be, and your engine runs hot (also first for me to read about). All probably linked to a bad set up, made worse by your tow speed.

I could flow chart how to regain safety, but you seem knowledgeable and know what to do. However, feel free to provide all loaded axle weights to be used with the hitch weight you already provided. I'll guarantee lots of help from this forum.

If you must tow this trailer, at 75 m/h, with the bed/cab load you described, then you either have the right truck (meaning pushing but not exceeding GVWR, less than 80% of GCVWR, and proper weight distribution), or you don't. If not, then check up, starting with the F150 diesel, then the Nissan 5.0 Cummins, and so on, until you are again safe and running your rig to last. Of course, I'll defer to those with specific vehicle criticisms, as I don't track them in fora, and haven't used them. Lastly, I benefit from not needing/wanting to go faster than 61-62 m/h, while towing my 21' Escape 5.0 TA bed hitch, with a loaded cab, filling the remaining bed volume, and a trailer with food, water, e bikes on back, other stuff. It's a whole different tow at 75, and if I was bound to go that fast I would have made a different tractor choice.

Not going to check again, but doesn't the new GMC 3.0 diesel feature lots of aluminum? If so, big down thumb from me. Yes, the aero diesels might be partly/mostly aluminum (and yes, they DO make them, for geographies without Av Gas access), and vehicles like my old BMW 650 Dakar had a converted aero engine. But airplane diesel conversions push 6 figures, so I'm guessing that a reliable aluminum truck diesel would almost double it's current price.

I am not the only one to mention that the exhaust brake does little to nothing on this site!
Check closer!!!
 

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I am not the only one to mention that the exhaust brake does little to nothing on this site!
Check closer!!!
Please read my post and show me where I said that. I have not read every post, so what I WROTE was "(first time I have seen this complaint, and mine is fine with a "heavy" tow)". In fact, I am sure that it is possible to overtow to such an extent. Any response to my actual points? If you dispute the basis for my safety request, let us see your axle weights. Who knows, I might be quite wrong....
 

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So the unfortunate thing is, exhaust brakes are not magic.

And second, there's nothing wrong with "revving the ****" out of modern diesel engines. I think I read one of the tuners state that in the engineering docs for these engines, the rotating assembly is good up to 6000 rpm. You wouldn't want to do that under load, and there's a fuel cutoff I believe at 4500... But under deceleration with no fuel, it's perfectly safe for the engine regardless of whether you agree or like it.
 

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Oh, and if you think the exhaust brake does nothing, let's prove it. If you're in southeast Michigan, we'll get trailers of equivalent weight and tow together. I'll use my exhaust brake, you don't, just regular engine braking, and we'll see who slows down more coasting downhill. By the way, that offer is only valid if you're in front of me.
 

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Oh, and if you think the exhaust brake does nothing, let's prove it. If you're in southeast Michigan, we'll get trailers of equivalent weight and tow together. I'll use my exhaust brake, you don't, just regular engine braking, and we'll see who slows down more coasting downhill. By the way, that offer is only valid if you're in front of me.
Well said, I was pulling a 28 foot trailer with 5 harley’s through the Rockies on a recent trip to Cripple Creek Colorado. The exhaust break worked like a champ. Very glad that I had it.
 
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