W124 Radiator Life Expectancy
 

My 94 E420 just passed the 100,000 miles mark, do I need to replace the radiator now or just wait till it break. As I recalled for my previous 89 300E, its radiartor failed around 100,000 miles. Luckily the car was not that far away from my garage, I managed to get there and have it replaced. I don't want that to happen on this car, especially if it happen out at nowhere. Any advice?

Wait til the engine cools, then pull the top radiator hose and look inside the neck to see if it is reinforced with a metal insert. If not, you're running on borrowed time...

Also do yourself a favor and carry a spare elbow for the return line that runs from the top of the radiator across the top to the reservoir. You will find it coming out of the radiator at top right when viewed from in front of the car. Should be in stock at the dealer for a couple of bucks.

It happened to me on one of my 300E's. On the interstate and all of a sudden steam and water shot out from under the hood. That little elbow had broken. I managed to rig up a temporary fix, but now have a spare just in case.


Steve

The broken neck did happen to my previous 89 300E, but that is way before the 100,000 miles mark. I think the later W124 should have the reinforced neck already. Now the question comes to the radiatot itself, how much longer can it last beyond 100,000 miles.

Time seems to have more of an affect then mileage. With my cars they seem to crack at around the 10-15 year mark.

I think the answer is it depends. If you do a lot of long distance travel I'd probably just do it proactivly as a preventive measure. If its an around town car wait.

I changed mine around 220,000 miles on a 1993 300e 2.8. Yours should have the reinforced neck already (mine did) other than that it probably will not be a catasrophic failure, just start to leak somewhere. You can buy one and keep it for peace of mind, it is really simple to replace.

Alex