Lysholm Master

Anyone have a thought on how many miles the water pump will last on an '08 ML550? The other day I noticed what appeared to be a little steam rising near the front of the hood. No visible leaks were apparent, but a few days later I got a warning on the dash to top up my coolant. I'm thinking that at 130K miles, it might be time for a preventative water pump / thermostat replacement. Waste of money or am I already on borrowed time with the water pump at this mileage?

ygmn

All depends on too many variables.

What fails is the seal and/or bearing and their life is crazy difficult to get accurate as it is based on Design, Flid flow pattern into bearing and seal area, RPM, load, temps, dirt, quality of coolant etc.

But anything over 100K is good and 200K is great and 300K is AWESOME

I have truck with over 165k and it is fine - 17 years old too...

Maj. Dundee

Hope you are not using GREEN coolant. If so flush the entire engine and radiator.

fabbrisd1

As a water pump fails - it leaks a bit - there is a "weep hole" on the underside of the pump - the OE "Graf" pump is cheap - like $110

I have found "many" failing water pumps have been caused/accelerated by failing belt tensioner - a OE equivalent belt tensioner like INA is like $90

The best thing to do is to replace both - and don't get faked in by low quality/cheaper parts/brands/non-brand/store-brand