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Short story and then a question. I'm driving down the freeway yesterday when the serpentine belt shreds itself into spinning strips of death, belt gets lose and car starts to overheat. Quickly pull to the side of the freeway and all of a sudden there's a loud bang and coolant shoots out from the left side of the grill, blowing over the hood and windshield. Get the car towed home, let it cool and look to see what the damage is. I don't know how, but the plastic left side of the radiator where the upper hose is connected to the radiator is cracked from the hose spigot pretty much up the entire side of the plastic tank. All I can think is that the serpentine belt shreds manged to smack against it enough to break it...whatever!
OK, pull the car apart, get the radiator out, sure enough crack is bad and many of the idler pulleys have been damaged with belt parts jammed behind the tensioner and its pulley. Order new radiator, pulleys, tensioner etc. *****, moan, complain...rinse and repeat!
So now my question. I didn't bother to look while I was under the car disconnecting the lower radiator hose. Is it the transmission oil cooler that's built into the radiator? If it is, has anyone considered bypassing that cooler and putting in an aftermarket cooler? My transmission temps run in the 212F - 221F (100C - 105C) range during daily driving, so I'm wondering if I could get those temps lower with an aftermarket cooler. Just looking for thoughts and opinions. Thanks.
You can get the temps lower but your range is pretty normal. Trans temps in modern cars run a lot higher than older cars. Mercedes along with all manufacturers today try to get all systems up to operating temperature as quick as possible to minimize emissions and maximize operating efficiency. The range you stated is pretty much in that sweet spot for normal driving in summer.
With that said, I spent a lot of money on upgrading my 7G with the Weistec kit plus converter. My original trans was fine but after adding the supercharger I wanted to make sure the rest of the drivetrain could handle spirited driving. I did two things to manage my trans temps for extreme conditions. The easiest upgrade is the Weistec trans pan. This aluminum pan has cooling fins and allows for additional fluid. The second requires more work and there isn’t an off the shelf solution. Weistec designed and installed a custom stand-alone pump and cooler that can be turned on manually or automatically.
These shots were during fitment/installation and little things like the long exposed bolts were properly sized when finished.
Also, as stated earlier, this is a custom installation that is not currently offered by Weistec or anyone else that I know of. If you contact them they know the car very well but may not be able to provide parts for this upgrade.
Cam, did you upgrade to the Weistec torque convertor? If so, how do you like the higher stall speed? Is it too much/high for regular non-spirited driving?
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