Update on Towing 7000# - '03 Chevy Avalanche 5.3 z-71

[pakman262]

Hello all:

As promised here is my report on towing my 31' Wilderness Yukon 830Y.

Just A reminder, my truck is a '03 Chevy Avalanche with the 5.3L Vortec and the 4.1 Axle. I also added the largest available transmission cooler and the Tekonsah Prodigy Brake Controller.

On my TT I installed a Hensley Arrow Hitch. I also had a custom built tray added to the rear of the TT to haul my Honda EU3000SI Generator. The added weight on the TT with these mods brings up the UVWR from the stickers claim of 5740# to 6285#.

This was my maiden voyage with a TT. Prior to this the largest trailer I have towed is a 14' U-Haul.

I towed the TT from Grapevine TX to Sierra Vista AZ using I-20 and I-10 and then AZ-90. As most of you probably know this route has some moderate to moderately severe grades specially on I-10 in Western NM and in Arizona.

In general, I was pleasantly surprised by the performance of the Avalanche. Being new to towing a trailer this large, I was determined to make sure that I travelled at speeds that allowed me ample saftey margins in case someone in front of me or to the side of me decided to play "super mario". As such I travelled mostly at speeds between 60 and 65MPH. On level to slightly inclined grades, I was able to maintain these speeds in OD and Tow/Haul mode with an RPM of around 2100 or so. On the days that we were travelling, their was a strong cold front moving in. This produced strong NW winds on Saturday and Sunday. At times when the travel direction was into the prevailing wind, I had to drop down to 3rd to maintain the same speed and resulting RPMs were around 2800.

I watched my engine temp and oil pressure like a hawk. The engine temp stayed rock steady at around 225 to 230, with 240 being the middle of the operating range.

When we got into the challenging grades in NM and AZ, I used the shift to shift down to 3rd in anticipation of middling grades and on two or three severe grades I had to shift down to 2nd to maintain a speed of around 50 MPH at the slowest.

So all in all, I would say I give the Chevy Avalanche a B to a B- for the towing performance. What gives me a lot of hope is that we had a lot of excess weight loaded on the truck, which will not be there on future trips. Given that fact, I would actually raise the grade to a B+.

Now a word on the Hensley Arrow Hitch: It is absolutely worth every $ I spent on it. Given the weather conditions that we travelled in and the heavy truck traffic, I am positive that I would have not been able to maintain safe control of the truck-TT combination anywhere near 65 MPH. At one point on Sunday morning, the TT was literally travelling behind me at a 10 to 15 degree angle because of the cross-wind, yet I was able to steer my truck with the lightest of hands on on the wheel. I even was able to take my hand-off the wheel momentarily to demonstrate the stability of the rig to my wife - don't try this at home without the Hensley!. There are very few products that exceed the advertising hype of the vendor....The Hensley definitely does that.

With regards to stopping power.... the Tekonsah Prodigy did a great job!. I literally felt that I was able to stop the combined vehicle in distances about close to the stopping distance of the truck by itself. Though I never allowed myself to be in a situation to prove that!

Finally about weights:
I did weigh the Truck and Trailer. With about 300# of Water in the tanks and about 300# of equipment on board the TT the trailer came in at 7000#. The truck was loaded down to an extra-ordinary degree and it weighed in at a whopping 7400#. Thus I was over the recommended max GCWR of 14000# by 400#. I immediately found a nearby dump location and got rid of the water, so the rest of the trip I was probably over by 100#. Given that in future trips I would expect my truck to be 500 to 750# ligher, I will be within the GCWR max, but not by much.

Now a question:

From time to time while towing we smelled a smell that was almost identical to the smell of LP Gas. We checked the trailer for LP leak and found none. Despite having the truck checked out by a GM dealer for any type of fluid leaks that could have burned-off to produce the smell and talking to several people who know a lot more about automobiles than I ever will, I have not found a satisfactory explanation for the smell. All fluid levels are okay and none of the fluids appear stressed. To confound matters, I have smelled the smell a few times while driving the truck without the trailer. Does anyone have any thoughts on this?

I hope I did not bore you with this lengthy post.

Thanks

The Pakman

[pakman262]

Hello all:

As promised here is my report on towing my 31' Wilderness Yukon 830Y.

Just A reminder, my truck is a '03 Chevy Avalanche with the 5.3L Vortec and the 4.1 Axle. I also added the largest available transmission cooler and the Tekonsah Prodigy Brake Controller.

On my TT I installed a Hensley Arrow Hitch. I also had a custom built tray added to the rear of the TT to haul my Honda EU3000SI Generator. The added weight on the TT with these mods brings up the UVWR from the stickers claim of 5740# to 6285#.

This was my maiden voyage with a TT. Prior to this the largest trailer I have towed is a 14' U-Haul.

I towed the TT from Grapevine TX to Sierra Vista AZ using I-20 and I-10 and then AZ-90. As most of you probably know this route has some moderate to moderately severe grades specially on I-10 in Western NM and in Arizona.

In general, I was pleasantly surprised by the performance of the Avalanche. Being new to towing a trailer this large, I was determined to make sure that I travelled at speeds that allowed me ample saftey margins in case someone in front of me or to the side of me decided to play "super mario". As such I travelled mostly at speeds between 60 and 65MPH. On level to slightly inclined grades, I was able to maintain these speeds in OD and Tow/Haul mode with an RPM of around 2100 or so. On the days that we were travelling, their was a strong cold front moving in. This produced strong NW winds on Saturday and Sunday. At times when the travel direction was into the prevailing wind, I had to drop down to 3rd to maintain the same speed and resulting RPMs were around 2800.

I watched my engine temp and oil pressure like a hawk. The engine temp stayed rock steady at around 225 to 230, with 240 being the middle of the operating range.

When we got into the challenging grades in NM and AZ, I used the shift to shift down to 3rd in anticipation of middling grades and on two or three severe grades I had to shift down to 2nd to maintain a speed of around 50 MPH at the slowest.

So all in all, I would say I give the Chevy Avalanche a B to a B- for the towing performance. What gives me a lot of hope is that we had a lot of excess weight loaded on the truck, which will not be there on future trips. Given that fact, I would actually raise the grade to a B+.

Now a word on the Hensley Arrow Hitch: It is absolutely worth every $ I spent on it. Given the weather conditions that we travelled in and the heavy truck traffic, I am positive that I would have not been able to maintain safe control of the truck-TT combination anywhere near 65 MPH. At one point on Sunday morning, the TT was literally travelling behind me at a 10 to 15 degree angle because of the cross-wind, yet I was able to steer my truck with the lightest of hands on on the wheel. I even was able to take my hand-off the wheel momentarily to demonstrate the stability of the rig to my wife - don't try this at home without the Hensley!. There are very few products that exceed the advertising hype of the vendor....The Hensley definitely does that.

With regards to stopping power.... the Tekonsah Prodigy did a great job!. I literally felt that I was able to stop the combined vehicle in distances about close to the stopping distance of the truck by itself. Though I never allowed myself to be in a situation to prove that!

Finally about weights:
I did weigh the Truck and Trailer. With about 300# of Water in the tanks and about 300# of equipment on board the TT the trailer came in at 7000#. The truck was loaded down to an extra-ordinary degree and it weighed in at a whopping 7400#. Thus I was over the recommended max GCWR of 14000# by 400#. I immediately found a nearby dump location and got rid of the water, so the rest of the trip I was probably over by 100#. Given that in future trips I would expect my truck to be 500 to 750# ligher, I will be within the GCWR max, but not by much.

Now a question:

From time to time while towing we smelled a smell that was almost identical to the smell of LP Gas. We checked the trailer for LP leak and found none. Despite having the truck checked out by a GM dealer for any type of fluid leaks that could have burned-off to produce the smell and talking to several people who know a lot more about automobiles than I ever will, I have not found a satisfactory explanation for the smell. All fluid levels are okay and none of the fluids appear stressed. To confound matters, I have smelled the smell a few times while driving the truck without the trailer. Does anyone have any thoughts on this?

I hope I did not bore you with this lengthy post.

Thanks

The Pakman

[6MISFITZ]

Congrats on a great sounding trip.

When we towed our old boat or hybrid TT (not at the same time) with our old Astro, there were smells that my wife had noticed from inside the Astro and mentioned to me.

One of the things we changed at the end of the first season of towing was the rear differential and transmission fluids. Neither was burned but after fresh fluid was put in, my wife made no more mention of any smells from normal town / city driving.

Rear axle lube (hypoid) when it does get hot could / may be similar to a propane smell. Hopefully, some other members can help with their experiences.

Because your trailer is a big one, I would suggest synthetic rear axle fluid to better cope with thermal extremes.

Too many new rv'ers experience buyers remorse on the first tow home from the dealers because of the ugly issue of sway that NO ONE warned them about, not even their dealer!
A Hensley Arrow is the top NO SWAY hitch on the market and you did yourself a huge favor by towing with this from DAY ONE. Great choice on that and the prodigy!

Yes, our tow vehicle's weight was an eye opener for us as well but now you have some hard numbers to use and plan for future trips.

Merry Christmas,
Season Greetings.
Mike.

[Disneydaddy]

Your trailer weight is close to mine (6400#) and our trucks are identical, glad to hear you werent too disappointed. I would however suggest that you use 3rd gear instead of OD, my understanding from many conversations is that the trans will not hold up if OD is used while pulling this big of a trailer. My personal experience is that it wont really stay in OD and it starts picking up and down between 3rd and OD. There is also a good arguement for increased lube and heat disipation when the trans is run at a higher input RPM. Also run the trans in tow/haul mode no matter what gear you use.
The rear end already has synthetic in it all you need to do is change it yearly with a synthetic 75w90

Scott

[pakman262]

Hello Scott:

Thanks for the info...what make and model trailer do you tow?

Since towing to Sierra Vista I have talked to many eperienced RV'ers and they all concur with your recommendation...namely avoid O/D. I do run in Tow/Haul. Thanks for the tip on changing the RE fluid yearly. I look forward to summer so we can hit the road.

Stay safe & Let the Good Times Roll!

The Pakman

[Jumbo Jet]

As far as the smell - could it have been the very hot smell of unleaded exhaust coming from the 5.3.

I have followed gas burners before that were pulling a load and the exhaust definitely takes on a different smell when you increase the amount of fuel being burned which also increases the exhaust gas temperatures.

There's nothing like a good romp out through the hills of NM and AZ.

[wingnut60]

I believe Jumbo Jet is right on the smell--I have been behind many newer GM products that seem to give off a 'propane' like exhaust smell.
It is probably the catalytic converter burning off the newness?