Do you suggest I replace water pump ?

No, I would not replace at that mileage. As others have said, they can go a LOT of miles. Only exception is if you know the coolant has been neglected over the coach's life-- if so, yes, change it out.

Assume you have the Cummins C engine-- water pump replacement is quite easy if you have a side radiator.

If it ain't broke...

Don't fix it.

There is no guarantee that your replacement pump will last longer. Mine is 19 years old with 97k miles and is the original.

88k and 12 years is nothing for a diesel's water pump.
I wouldn't touch it.

I would change the belt and all the hoses.

allbrandauto wrote:
IT PROBALY DID NOT HURT BUT AS A AUTO REPAIR SHOP AFTER MARKET WATER PUMPS DONT LAST WOULD DO IT WIHT OEM PUMP

Why are you yelling? :?

I would replace the water pump, fan belts, and replace the heater hoses with the newer braided silicone hose material now available. The silicone hoses do use a slightly different hose clamp. Since you already have everything apart, and because of the high mileage, I would do it now at the comfort of your own house. Maybe new radiator hoses also.

IT PROBALY DID NOT HURT BUT AS A AUTO REPAIR SHOP AFTER MARKET WATER PUMPS DONT LAST WOULD DO IT WIHT OEM PUMP

Although there is probably nothing wrong with it, it's much easier and cheaper than doing it on the road. It does have a lot of miles and I would probably change it out.