Babyfood1217
Member
After purchasing my 2002 sport edition 4runner last spring, one of the additional preventative maintenance items I acted on was the install of an auxiliary transmission cooler, so as to never have to worry about the pink milkshake. Install went fine, and I've put a number of miles on it, without issue. Last weekend, however, I experienced a fluid leak, and a major one at that.
After making an abrupt U-turn and some back/forth shimmying to sneak into the only parallel parking spot in my neighborhood, I exited the truck to see a trail of fluid on the ground. It started about 10 yards up the road, and followed my exact path, including U-turn and shimmying. Had it been a raging hot day, perhaps the A/C condenser could provide some fluid, but this day was cold, and there was way too much to be just water even if the A/C had been on. A closer inspection under the truck revealed a pool forming under the passenger side of the radiator, and even closer inspection revealed it was transmission fluid.
Needless to say, I went with my departing friends and nursed the impending doom with a sazerac, an Olympia, and some Yukon Jack, and went back to the truck. With the vehicle off, it appeared the leak has stopped (not before creating quite the puddle.) I check the transmission dipstick and determined there was still enough fluid to drive the 1.5 miles home. Carefully. Cautious and attentive driving got me home, where I check the fluid level, and at warm temps, the level measured just below the "cold" marks. Not having time to deal with it that night, the morning brought me to pulling my grille off to see what happened.
Low and behold, a hose clamp broke. The hose clamp on the lower end of the aux. cooler (I don't recall if this is in-flow or out-flow) had broke, mid band, right where a hole had been stamped in the strap. Upon removing the broken clamp, I also found a second fatigue crack starting in the slotted portion of the clamp (the part the screw catches.) Luckily, I had a couple extra hose clamps of the same size, and was able to install. The new clamp looked a little nicer, and perhaps beefier. It was stamped "Tridon" vs. the broken "NAPA" one. Not sure where I got the NAPA one. I don't shop their. I believe the TRIDON clamps were what came with the aux. cooler.
After installing the new clamp, I did a cursory inspection for any other possible sources of the leak. After finding no other issues, I began refilling the fluid. Not knowing how much I really had lost, but expecting a decent amount, I performed a number of fills, transmission cycles, waits, and checks. Volumes looked good, and then I would do some driving around the nearby neighborhood, and post-drive volumes would be remarkably low. In all, I put more than 3.5 qts in to yield the proper volume at "hot" temps. I know most people usually only get 3.5 qts out during a drain refill, but I imagine there was still fluid in the torque converter/hoses, and the aux. cooler itself that likely saved my from totally running dry.
Now, I'm totally paranoid about the stupid hose clamps I use. I'm tempted to buy wire hose clamps and swap them in wherever I have a strip one.
Needless to say, I will be adding a few different sizes to my on-board spare kit.
I feel like my truck had a brush with death, and really fortunate timing led to it's salvation.
Moral of the story: check little things every once in a while.
After making an abrupt U-turn and some back/forth shimmying to sneak into the only parallel parking spot in my neighborhood, I exited the truck to see a trail of fluid on the ground. It started about 10 yards up the road, and followed my exact path, including U-turn and shimmying. Had it been a raging hot day, perhaps the A/C condenser could provide some fluid, but this day was cold, and there was way too much to be just water even if the A/C had been on. A closer inspection under the truck revealed a pool forming under the passenger side of the radiator, and even closer inspection revealed it was transmission fluid.
Needless to say, I went with my departing friends and nursed the impending doom with a sazerac, an Olympia, and some Yukon Jack, and went back to the truck. With the vehicle off, it appeared the leak has stopped (not before creating quite the puddle.) I check the transmission dipstick and determined there was still enough fluid to drive the 1.5 miles home. Carefully. Cautious and attentive driving got me home, where I check the fluid level, and at warm temps, the level measured just below the "cold" marks. Not having time to deal with it that night, the morning brought me to pulling my grille off to see what happened.
Low and behold, a hose clamp broke. The hose clamp on the lower end of the aux. cooler (I don't recall if this is in-flow or out-flow) had broke, mid band, right where a hole had been stamped in the strap. Upon removing the broken clamp, I also found a second fatigue crack starting in the slotted portion of the clamp (the part the screw catches.) Luckily, I had a couple extra hose clamps of the same size, and was able to install. The new clamp looked a little nicer, and perhaps beefier. It was stamped "Tridon" vs. the broken "NAPA" one. Not sure where I got the NAPA one. I don't shop their. I believe the TRIDON clamps were what came with the aux. cooler.
After installing the new clamp, I did a cursory inspection for any other possible sources of the leak. After finding no other issues, I began refilling the fluid. Not knowing how much I really had lost, but expecting a decent amount, I performed a number of fills, transmission cycles, waits, and checks. Volumes looked good, and then I would do some driving around the nearby neighborhood, and post-drive volumes would be remarkably low. In all, I put more than 3.5 qts in to yield the proper volume at "hot" temps. I know most people usually only get 3.5 qts out during a drain refill, but I imagine there was still fluid in the torque converter/hoses, and the aux. cooler itself that likely saved my from totally running dry.
Now, I'm totally paranoid about the stupid hose clamps I use. I'm tempted to buy wire hose clamps and swap them in wherever I have a strip one.
Needless to say, I will be adding a few different sizes to my on-board spare kit.
I feel like my truck had a brush with death, and really fortunate timing led to it's salvation.
Moral of the story: check little things every once in a while.
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