GM Truck Club
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 6 of 6
  1. #1
    Jr. Apprentice
    Join Date
    Jun 2006
    Ravenstown Maryland

    Default 98 K-1500 losing antifreeze

    My 98 K-1500 is losing antifreeze it is not going on the ground or into the oil. I have already replaced the intake manifold gaskets about 2 years ago also the water pump and all of the hoses. when under the hood when engine is hot you can smell the antifreeze but you just can't see where it is leaking from. any suggestions? Truck has 121,000 miles.


  2. #2


    Check the radiator cap and radiator itself. Could be a leak that's too small to puddle, but sprays out and evaporates.

    99 K 1500 Suburban
    78 Silverado Big 10 w/factory 454
    00 S-10 Blazer
    1976 Trans Am
    1980 Honda CB900 Custom

  3. #3


    The first thing I would do would be to put a cooling system pressure tester (you can borrow one from Autozone) on it and pressure up the system cold. As GaryL noted, sometimes these leaks are so slow that the coolant evaporates before you have a chance to see it. Pressuring up the system cold will allow any external leak to drip or puddle somewhere where you can see it.
    '98 K1500 Suburban LS 5.7 L 4L60E NV246 ARB
    '92 Ford Explorer XLT 4x4 4.0 L A4LD BW13-54 Trac-loc rear
    "My toys were the greasy cogs and springs and pistons that lay around all over the place, and these, I can promise you, were far more fun to play with than most of the plastic rubbish children are given nowadays." Danny in Roald Dahl's Danny The Champion of the World

  4. #4


    my 97 had the same problem and finally found the culprit, especially if you smell antifreeze as if it was leaking on the hot engine. The hose that goes into the top of the front right, passenger, side of the engine is only held in with a plastic snap clip and is sealed by one or two O-rings, you can buy a replacement clip and holder at any of the auto stores, you dont have to replace the hose. Most of them come with the fitting that also threads into the block, just use caution to remove the old fitting and use sealant when you thread the new one in. remember, the clip just snaps in.

  5. #5


    Don't forget to check the transmission fluid. It's uncommon nowadays but your transmission cooler is inside your radiator and coolant can seep into the transmission if the cooler cracks open. Sometimes it's a very small leak and only happens hot. You will see evidence on your transmission dipstick and the ATF will turn into a strawberry milkshake. <don't drink it!>

    2004 SILVERADO 2500HD LS
    Pro Comp Leveling Kit
    285-75-16 Cooper ST All Terrains
    Pro Comp Programmer
    Bilstein Shocks
    Linux Bed Liner
    Tinted Windows

    Other rides:

    1967 Landcruiser <350 Chevy>
    1970 Camaro
    1990 Geo Metro Convertible
    2007 FJ Cruiser

  6. #6


    how about you heater core? probably not, but check on the floor or under the dash on the passenger side for signs of coolant

Similar Threads

  1. antifreeze leak?
    By dshewy14 in forum General Chevy & GM Tech Questions
    Replies: 7
    Last Post: 03-15-2010, 11:28 AM
  2. 350 antifreeze leakage
    By Aubio in forum General Chevy & GM Tech Questions
    Replies: 2
    Last Post: 02-08-2010, 08:25 PM
  3. Leaking Antifreeze
    By 913projectchevy in forum General Chevy & GM Tech Questions
    Replies: 7
    Last Post: 11-23-2009, 10:44 AM
  4. antifreeze leak
    By Brent0644 in forum General Chevy & GM Tech Questions
    Replies: 4
    Last Post: 10-24-2009, 09:14 PM
  5. Spot of antifreeze
    By danman5000 in forum GM Powertrain
    Replies: 2
    Last Post: 10-08-2009, 06:13 AM

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