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Towing with built trans and tuner?

2K views 7 replies 5 participants last post by  dieseltherapy 
#1 ·
I am looking at purchasing a revmax 550 and will be tuning the truck. My question is, for those of you that have a built transmission, are you towing on the lower tune settings? Or are you towing on the 100+ hp tunes. In a perfect world if you had no risk of hurting the trans, is there any advantage to towing in the lower hp settings?
 
#2 ·
Lower power setting is generally less fuel for longer rpm ranges, which means less heat. Less power also means less effect of torque limiting (defueling) during shifts so easier on driveline hard parts. Less torque limiting also means less stress on the torque converter clutches during locking and unlocking, less stress on clutch packs during shifts in lower gears, and much less stress on clutch packs in general (particularly the overdrive gears). If there’s a tune level labeled “towing”, it’s probably a safe bet the tuner has done their research and is comfortable saying that’s a safe power level at which to tow within the factory load rating of the vehicle. And if it’s an ok tune for a stock trans, it’ll definitely be ok for a built trans.

Are you asking if it’s ok to run the engine at the max rated power of the trans all the time regardless of what you’re doing? I think your best bet would be to call the tuner and get an updated tune with a built trans factored in. Pretty sure several of them have torque limiting function still enabled in all but the race (aka “break stuff and blow s— up”) tune.

Also probably worth a call to revmax. They’re racers and hot-rodders; they get it... they know we lay out money to buy parts with full intentions of beating the ever-loving snot out of them.


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#3 ·
A little background may be helpful. I have several service trucks with enclosed bodies, but I also have a personal truck 2014 w/g56 I use for towing/ family trips etc it has a 60hp tow tune, which I am happy with, and is about all the stock clutch can handle. I purchased a 2009 CTD w/ wrecked bed, and a bad transmission. My intention is to basically turn it into my towing truck/ play truck. So far I have spoken with revmax twice, and I am pretty set on their 550. I will be deleting the truck, and most likely run the tow tune. I am not a believer in constantly switching tunes I just like to get it tuned and be done. So the reason for my question is if I am going to spend the cash to have a built trans, is there any advantage to running a hotter tune than the tow setting all the time? Even while towing? I obviously do not want to wreck any parts, but I have been known to have alittle fun. I am very observant while towing though, that's why I like a manual rig.


I guess the root of my question is, If you are towing say 10,000lbs, and you have a tuned truck with a built transmission, is it equally reliable at 100hp as 60hp? Theoretically (in my mind) it would tow better with more power, but as you stated above, at the cost of more stress on the truck. I am looking for a good balance of power and reliability, but also would want to take advantage of the $6k price tag on a built trans.
 
#4 ·
If you have not already bought a tuner, why not just get a EFI Live with a CSP5 switch. 5 tunes, available on the fly with the turn of a dial. Turn it down for towing, turn it up a little for daily driving, and turn I way up when you're feeling frisky.
 
#5 ·
What are you towing exactly?

My combined weight when towing is around 33,000 pounds. I drop my BlackMaxx tune to MILD. Tow with a heavy horsepower tune and you will roast stuff, trust me on this.
 
#6 ·
Thanks for the info. I was under the impression that switching tunes was not good for the trans.

Towing an enclosed trailer with sales displays in it. I believe it’s an 8x30 weight is right around 10k. That is typically as heavy as I tow, other than an occasional piece of equipment.
 
#7 ·
So, you are towing the equivalent of my dually. I know the 68RFE is sensitive to change tunes/power levels because some tuners will reset the trans values and can roast the transmission.

If you are only towing ~10k, likely no worries for you. Tow awayl No racing while you're towing, eh?
 
#8 ·
I have a category 5 trans from suncoast that PO put in to tow REALLY heavy stuff. Truck was worked hard for awhile until I bought it at 163k miles. It has an H&S tuner on it since 2012 and I've continued to use it the last year I've owned. I saw my egts get higher than I liked towing on the 120hp setting when I tried towing with it set a little hotter so I always tow on 60hp over stock and no more.
I also like to the rule of towing at mild setting (60hp) and daily it on (120hp) with an occasionally feeling frisky bump up to 175hp) over stock and I've really enjoyed this truck more than any other. So I try to be smart bc I can't afford for the suncoast to take dump just because I want to tow on a high hp setting.

On my 60hp setting I pullled about a 6 mile stretch at about 4-5% grade only grossed out at about 14k including truck and I go WOT and let it eat at about 70mph at the bottom and when I get to the top I'm going about 69mph.
EGTs are usually 1100-1150 all the way. That impresses the heck outta me.
 
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