Preventative maintainance

[fourtenposi]

Hello All,

Have have a 2005 GMC 2500HD D/A LLY truck. It is rolling up on 100,000 miles. It has been a good truck thus far. So I am thinking, what are the thinking that typically start going wrong in this mileage range?

Truck has been great, I think other than the standard maintenance, only thing I had to replace was a leaking power steering line.

I was reading that GM used some plastic impellers on there water pumps which eventually start spinning on the shaft. I know AFE sells an after market pump with a metal impeller that is tig welded to the pump. Anyone have any experience with this? I haven't experienced any over heating issues, but I have noticed that I see some fluctuation in water temp. For example, all of sudden temp will drop 20-30 degrees. Should I put a new pump on it? I did put new thermostats in with no change.

So what should I be looking at?

Thanks in advance!

[lmholmes11]

1. Replace Serp Belt every 5 years or 100K miles (if you haven't already done it. Also spin all the pulleys by hand and replace all that need to be replaced.

2. Test batteries because one weak battery can cause some wierd issues.

3. Inspect the rear half of the T/C and make sure there's not a pin sized hole forming from the common pump rub issue. Merchant Automotive sells a pump upgrade kit for a little over $100 that will take care of the issue so you don't have a hole form, run your transfer case out of fluid and have it grenade while going down the road

4. As for the water pump, I'd make sure your gauge is reading right before you go tearing your water pump out in my opinion.


These are the first ideas that come to mind. You should also probably do a trans fluid flush and both diffs also.

[More Power]

I was reading that GM used some plastic impellers on there water pumps which eventually start spinning on the shaft. I know AFE sells an after market pump with a metal impeller that is tig welded to the pump. Anyone have any experience with this? I haven't experienced any over heating issues, but I have noticed that I see some fluctuation in water temp. For example, all of sudden temp will drop 20-30 degrees. Should I put a new pump on it? I did put new thermostats in with no change.

So what should I be looking at?

Thanks in advance!

The performance aftermarket began offering welded impellers on water pumps because of failures in high-horsepower or competition engines. I haven't heard of one failing otherwise.

As long as the water pump isn't leaking or making some bad noises, I'd run it till it does fail. From a seal life perspective, these pumps should run for a few hundreds of thousands of miles as long as the engine doesn't suffer from a cooling system overpressure problem.

Jim