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Towing After Blackbear Tune

Z71-K9

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Z71-K9 Enthusiast

Z71-K9

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The question was asked over in the Pittsburgh thread but I didnt want my answer to be buried. Anyways, I just got in from the Indy 500. I kept pretty good records of the trip.

 

Truck is an 2007 VMax with the "Max Trailering Package". For those not familiar; 9.25 rear diff., 4.10 gears, G80 locking diff., four wheel disc brakes, 6.0 motor, and heavy duty 4spd auto.

 

Tune: Justin tuned my truck May 3 and I had approximately 300 miles on it before the trip. The tuen was setup for 91 octane but I have running 93. I Justin's recommendation, when towing I changed out the performance TCM for the stock one. Tow/Haul mode as factory normal and used the entire trip. A/C on the entire trip.

 

Trailer is approximately 6500-7000 lbs. loaded.

 

I drove west on Rt. 76 to I-70 going on I-470 around Wheeling. I-470 has two 4% 3 mile grades. Trip was 1,025 miles roundtrip.

 

Last year same route without the tune I got 7.5mpg with some sections of Ohio getting as high as 12mpg. I did not have an average for last year's trip.

 

This year after the tune. Considerable notice in takeoff and acceleration. Comes up to speed quickly and most impressed with how quite it runs. Shifts wonderful. Much easier to tow. Speeds were kept around 65mph with passing done around near 75mph. Sweet spot seemed to be around 60 or 62mph. I averaged 8.5mpg for the entire trip with some parts of I 70 west of Columbus getting 15mpg in V4 mode for several miles.

 

Tranny temps were closely monitored. Temps ran from 181 to 210. Average was probably 190. Coming up those hills outside Wheeling brought the temps up to 210 but quickly dropped back down once the truck shifted into the next higher gear.

 

Overall, Justin gets 2 thumbs up! Truck is a bigger winner in my book.

svensk Senior Enthusiast

svensk

Posted
Posted

On your tuned TCM did Justin perform changes to the tow/haul mode? Because I'm wondering why bother putting the stock one back in just to use tow/haul mode anyways?

brims Senior Enthusiast

brims

Posted
Posted

Since I don't tow at all for now, Justin made Tow/Haul a "performance mode", he said if I tow to just swap the stock TCM back in and you get the stock shifting with the better engine performance.

Z71-K9 Enthusiast

Z71-K9

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Since I don't tow at all for now, Justin made Tow/Haul a "performance mode", he said if I tow to just swap the stock TCM back in and you get the stock shifting with the better engine performance.

 

 

I only tow once a year so we set up my TCM the same.

brims Senior Enthusiast

brims

Posted
Posted

I forgot to ask him what exactly the new performance mode will do, I've hit the button and couldn't feel a difference.

MS3DALE Senior Enthusiast

MS3DALE

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I forgot to ask him what exactly the new performance mode will do, I've hit the button and couldn't feel a difference.

 

He set mine up the same way,I can notice a difference though!!! :(

brims Senior Enthusiast

brims

Posted
Posted
I forgot to ask him what exactly the new performance mode will do, I've hit the button and couldn't feel a difference.

 

He set mine up the same way,I can notice a difference though!!! :(

 

 

I was playing with it today, it just seems to shift the tranny at a higher RPM under partial throttle. Which is what the regular Tow/Haul mode does, it may do other things as well with the tranny but I'm not sure.

The Chosen One Enthusiast

The Chosen One

Posted
Posted

i read somewhere that tow/haul was to be set on higher octane and that is where you are suppose to notice the difference. dunno? but my intentinos are to set mine up that way when he comes into town next month.

brims Senior Enthusiast

brims

Posted
Posted
i read somewhere that tow/haul was to be set on higher octane and that is where you are suppose to notice the difference. dunno? but my intentinos are to set mine up that way when he comes into town next month.

 

I could be wrong, but I think the tow/haul button only changes transmission parameters.

 

There are 2 spark tables, high and low octane. The computer constantly changes what spark advance it's going to use based on those 2 tables, crap gas is going to use the low octane, better gas/higher octance gas is going to use the high octane table, gas inbetween will use spark advance somewhere between those 2 numbers.

66nova Senior Enthusiast

66nova

Posted
Posted
i read somewhere that tow/haul was to be set on higher octane and that is where you are suppose to notice the difference. dunno? but my intentinos are to set mine up that way when he comes into town next month.

 

I could be wrong, but I think the tow/haul button only changes transmission parameters.

 

There are 2 spark tables, high and low octane. The computer constantly changes what spark advance it's going to use based on those 2 tables, crap gas is going to use the low octane, better gas/higher octance gas is going to use the high octane table, gas inbetween will use spark advance somewhere between those 2 numbers.

 

 

You are correct. The tow/haul mode only changes the tranny. What Justin normally does (and I'm sure there is more to it then this) is changes the shift points and removes all of the torque management for the "race mode" tow/haul. With just normal driving you will not really notice a difference, but under W.O.T. you should notice a difference especially if you have at the track or use a GPS performance system (G-tech or iphone).

 

I tow a lot so I did just opposite of what most do. I removed all of the TM in regular mode and left all of it in Tow/Haul. My foot is the TM.

MS3DALE Senior Enthusiast

MS3DALE

Posted
Posted
What Justin normally does (and I'm sure there is more to it then this) is changes the shift points and removes all of the torque management for the "race mode" tow/haul. With just normal driving you will not really notice a difference, but under W.O.T. you should notice a difference especially if you have at the track or use a GPS performance system (G-tech or iphone).

 

^^Yep,This is what he did to mine^^

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