Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

700R4 Overflow

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by corvette6, Mar 9, 2001.

  1. corvette6

    corvette6 Registered Member

    Joined:
    Mar 9, 2001
    Posts:
    12
    Likes Received:
    0
    I'm having some problems with my 700r4 puking fluid all over the place when i'm towing or at high speeds. I'm looking for advice from someone who has experienced the same problems. My tranny was rebuilt about
    30k ago. I recently had the pan dropped by the shop that rebuilt it for me. The fluid was toasty but no noticeable debris. I have a large three core radiator with an auxilary cooling fan and a large tranny cooler. The truck has a 300hp small block, 3.08 gears and 33 inch tires and the temp always stays below 200 degrees and usually closer to 180.

    The problem i'm having is when towind in drive with the converter
    locked up. After driving for a while at 50 or 60 with my trailer behind it (5000
    lb) it sprays fluid all over the exaust. By the time I pull over to the side
    of the road, no more fluid spraying just smoke. Then I can get right back in
    and drive another 30 to 60 miles before it happens again.

    I'm not sure where to go next. Can I make this tranny work for towing?
    Do I need a bigger radiator, bigger tranny cooler or fan on tranny cooler or anoverflow tank for the tranny fluid?

    I'm pretty frustrated and seriously considering a 350 or 400. The only
    time I drive any distance is when i'm towing and I can't tow in overdrive...

    Thanks in advance for any help or insight
    Elliot

    Could you please email any response to corvette6@netzero.net
     
  2. corvette6

    corvette6 Registered Member

    Joined:
    Mar 9, 2001
    Posts:
    12
    Likes Received:
    0
  3. corvette6

    corvette6 Registered Member

    Joined:
    Mar 9, 2001
    Posts:
    12
    Likes Received:
    0
    I know i'm a newbee to the list, but this has got to be common problem. Can I solve it or do I need to replace the tranny with something more durable?
     
  4. coopertwpk

    coopertwpk 1/2 ton status

    Joined:
    Mar 18, 2000
    Posts:
    478
    Likes Received:
    0
    Location:
    Spring Valley Lake Ca.
    sounds strange I think the trans shop should check it out do you have a tranny temp gauge ?another guy tried extening his vent tube up into the engine area into a small oil sump so it would vent then drain the fluid back into the tranny .

    88k5 silverado w4"lift soon to have <font color=orange>d44 and corp14ff</font color=orange> with 4.56s
     
  5. corvette6

    corvette6 Registered Member

    Joined:
    Mar 9, 2001
    Posts:
    12
    Likes Received:
    0
    I don't have a temp gauge, but the engine temp and tranny cooler lead me to beleive it is running as cool as can be expected. I saw a webpage about motorcoaches and they mentioned an overflow for the tranny to keep it from spaying on the exhaust and causing a fire. Did this work for the person who tried it on a K5?
     
  6. gokartergo

    gokartergo 3/4 ton status Staff Member Moderator

    Joined:
    Dec 2, 2000
    Posts:
    5,855
    Likes Received:
    0
    Location:
    Hollister, CA
    On the passenger side of the tranny there is a sensor. I forget what it does. I think it was a overdrive sensor. When I put the new motor in some how I had hit it. And loosened the wires. I went down and bought a new sensor and it was fine after that. The only time it would leak is when I was driving in overdrive. Which isn't that often. Hope it helps...

    Become one with nature............Then marinate it...
     
  7. dyeager535

    dyeager535 1 ton status Premium Member

    Joined:
    Dec 13, 2000
    Posts:
    26,980
    Likes Received:
    189
    Location:
    Roy WA
    I can't comment on the fluid..you shouldn't be heating it enough to spew out the vent I would imagine, without imminent tranny failure.

    I CAN say that with 3.08's, 33" tires, and the load you are towing, if you aren't driving it like a manual tranmission (downshifting manually) you are really putting a load on that tranny. How is your tranny cooler plumbed? Through the radiator then cooler, or just to the auxiallary cooler?


    Dorian
    My K5 and Chev/Olds tech/links page: <A target="_blank" HREF=http://www.dorianyeager.com/index2.html>http://www.dorianyeager.com/index2.html</A>
     
  8. Thunder

    Thunder 3/4 ton status

    Joined:
    Jul 20, 2000
    Posts:
    8,946
    Likes Received:
    1
    Location:
    Northeast Nevada
    It sounds like you are overheating the trans. With 308 gears , 33" tires, and a 5000 lb trailer you are putting a real heavy load on that 700r4.The size of your cooler will not help if your tranny is overworked. I would change your gear ratio to 375 or higher or go back to smaller tires when you tow.
    Also never tow with a 700r4 in overdrive.
     
  9. fad2blk99

    fad2blk99 1/2 ton status

    Joined:
    Feb 19, 2001
    Posts:
    860
    Likes Received:
    0
    Location:
    Charleston, SC
    Okay... I had the exact same thing happen to me. I was goin about 75mph and over the course of about 7 miles I lost every bit of fluid in the tranny. I think my problem as due to a deep water crossing a week or so earlier. Either way, I'd had enuff w/ the problematic 700r (third rebouild in a year) and swapped in a Muncie 4sp. I talked to everyone who knew anything about the 700 and they were baffled. I do think the gear ratio-to-tire combo you're running has a lot to do w/ it. I was running 31's w/ 308's at the time of my tranny's demise and some people were sayin that had a lot to do w/ my frequent rebuilds. Hope some of this info helps. Good Luck!! -Tommy
     
  10. dyeager535

    dyeager535 1 ton status Premium Member

    Joined:
    Dec 13, 2000
    Posts:
    26,980
    Likes Received:
    189
    Location:
    Roy WA
    Ok, one other thing I thought of, are you SURE of where it is coming out from? I'm not so sure this would be an intermittent spewing like you are experiencing, but the 700R4 can push the front seal out of the transmission...I could maybe see the fluid getting thin enough as it heats up to start leaking...sorry, still no absolutes.

    Dorian
    My K5 and Chev/Olds tech/links page: <A target="_blank" HREF=http://www.dorianyeager.com/index2.html>http://www.dorianyeager.com/index2.html</A>
     

Share This Page