GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 7 of 7

Hybrid View

  1. #1

    Default Towing in a non-standard configuration

    Well, tommorow I'm going to be picking up a trailer that weighs around 3000 pounds. No big deal, except I'm still running in my slightly screwy transmission cooler setup. My 700R4 transmission is getting cooled only by an auxillary transmission cooler, and has been since I replaced the transmission. When I replaced the transmission, I pulled the radiator cooler out of the loop in a fit of being an idiot. I haven't had any issues with it, but this is the first moderately heavy trailer I'm pulling with the truck since then. So the question is, is my aux transmission cooler at least as good as the factory cooler that would be in the radiator? If so, I think I'll be fine towing this trailer as the specs for the truck list that there's no special options needed to tow up to 3000 pounds.\

    Also, could I/should I tow this trailer in overdrive? I am pulling the trailer around 4.5 hours one-way and overdrive would really help on fuel mileage if I don't burn the transmission up in the process? It seems like the trailer should be light enough not to cause an issue, but cooking a tranny is a VERY unattractive option.

    Thanks!
    Christopher

    1991 Chevy Suburban 1/2 ton 2WD w/ chevy SBC 350-3/4 ton drivetrain upgrade w/4.10 gears 200K miles
    2005 Saturn ION-2 Stock 265K miles
    1982 Bronco, 1993 Bronco (sold), 1971 M35A2 Deuce and a Half



    There are 10 kinds of people, those who understand binary, and those who dont...

    Remember kids, the only difference between screwing around and science is writing it down- Adam Savage

  2. #2
    Legend

    Join Date
    Jun 2006
    Location
    River Ridge Louisiana-4 miles W of New Orleans-didn't flood-water stopped 800 yards away.
    Posts
    1,612

    Default

    Crawdaddy
    I would pass on the overdrive.
    True it might get you another mpg-but not worth the risk
    I would guess at 60 mph towing in OD might get you 9-10 mpg vs 8-9 mpg

    Is your aux cooler sorta in the breeze-with a clear shot at incoming air- ?
    I would bet the aux cooler would work just fine- might even have more surface area than the stock setup.
    Of course there is a lot to be said for OEM setups-engineers usually know their business and the stock setups are usually pretty clean looking.
    I know the feeling of having an attack of "seemed like a good idea at the time" sorta thing.
    I wouldn't use the OD- aftermarket cooler should work ok.Temp gauge??
    How many RPMs does it turn in OD vs 3rd-maybe 1800 vs 2300 rpms?
    Luck
    Charlie
    1998 suburban-
    1/2 ton

    199500 miles
    River
    Ridge,LA

  3. #3

    Default

    It's not a great pic, but it's all I have at the moment. This is a pic of the cooler behind the grill:


    And here's the whole thread on the install of the cooler:
    http://www.gmtruckclub.com/forum/sho...n-Fluid-Cooler

    I'd say that when I'm on the highway (90% of the trip), it has plenty of breeze. I'm not sure of the RPM difference because the truck doesn't have a tach, but the overdrive gear in 700R4s is pretty steep, something like a .73 ratio vs the 1 for 3rd gear.
    Christopher

    1991 Chevy Suburban 1/2 ton 2WD w/ chevy SBC 350-3/4 ton drivetrain upgrade w/4.10 gears 200K miles
    2005 Saturn ION-2 Stock 265K miles
    1982 Bronco, 1993 Bronco (sold), 1971 M35A2 Deuce and a Half



    There are 10 kinds of people, those who understand binary, and those who dont...

    Remember kids, the only difference between screwing around and science is writing it down- Adam Savage

  4. #4

    Default

    Well, apparently the truck can tow that 3000 pound trailer with just the small auxillary cooler pictured. We towed in 3rd gear with an average speed of 55-65mph. At every fuel stop I checked the level, color, feel, and smell of the transmission fluid. The level stayed great the whole trip and the feel of the fluid was consistent. The fluid got a little less red and more transparent as time went on. It also started to smell less strong, but never picked up a burnt smell to it. Touching the exposed pipe bends of the cooler gave me between a 1.5 to 2 count before I had to remove my hand. No slipping was detected in the transmission while towing.

    That said, I'm now going to get the cooling system set up how I really want it, going into an external transmission fluid filter, going through the radiator cooler, then to the biggest B&M cooler available. I'm also going to do a fluid swap in the transmission and new filter, and possibly a new deeper transmission pan with a bung for a temp sensor.
    Christopher

    1991 Chevy Suburban 1/2 ton 2WD w/ chevy SBC 350-3/4 ton drivetrain upgrade w/4.10 gears 200K miles
    2005 Saturn ION-2 Stock 265K miles
    1982 Bronco, 1993 Bronco (sold), 1971 M35A2 Deuce and a Half



    There are 10 kinds of people, those who understand binary, and those who dont...

    Remember kids, the only difference between screwing around and science is writing it down- Adam Savage

  5. #5
    Legend

    Join Date
    Jun 2006
    Location
    River Ridge Louisiana-4 miles W of New Orleans-didn't flood-water stopped 800 yards away.
    Posts
    1,612

    Default

    Crawdaddy
    Great
    What sort of mpg did you get?
    The cooler looked like it was maybe 8" by 12" ?? Decent sized, but the bigger the better in south louisiana/Miss. summers
    So you will set it up to be double cooled-OEM setup thru radiator then a big aftermarket one-with a way to measure temp?

    One to two seconds sounds fairly cool- bet that is under 200 degrees? 200 degree metal is plenty hot.
    Charlie
    1998 suburban-
    1/2 ton

    199500 miles
    River
    Ridge,LA

  6. #6

    Default

    I averaged 12-13 mpg. The trip out empty to pick the trailer up didn't yield the 15 mpg I got when driving it to work for a week, but I still consider the mpg good. The trailer was taller than the truck and had a front wall on it, so it had considerable wind drag.
    Christopher

    1991 Chevy Suburban 1/2 ton 2WD w/ chevy SBC 350-3/4 ton drivetrain upgrade w/4.10 gears 200K miles
    2005 Saturn ION-2 Stock 265K miles
    1982 Bronco, 1993 Bronco (sold), 1971 M35A2 Deuce and a Half



    There are 10 kinds of people, those who understand binary, and those who dont...

    Remember kids, the only difference between screwing around and science is writing it down- Adam Savage

Similar Threads

  1. Standard transmission for 89 1/2 ton 4x4 Sbn
    By Slim57 in forum Chevy Suburban Forum (GMC Yukon XL)
    Replies: 3
    Last Post: 08-03-2011, 03:05 PM
  2. Sub in a standard cab Silverado
    By sollucho in forum Audio, Video & Gadget Tech
    Replies: 0
    Last Post: 10-07-2010, 04:11 PM
  3. Standard Transmission ID
    By jtiffany78 in forum GM Powertrain
    Replies: 3
    Last Post: 05-31-2010, 12:24 AM
  4. Configuration
    By piperdriver in forum Chevy Silverado Forum (GMC Sierra)
    Replies: 2
    Last Post: 02-22-2010, 03:05 PM
  5. 07 Silverado Z71 VS standard suspension
    By zekeman in forum Lifted & Offroad Suspension
    Replies: 4
    Last Post: 08-15-2008, 10:20 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •