High mileage maintenance?

gtocato · 07-29-2008, 06:12 PM

I have a 1997 6.5 Turbo 2 door Tahoe with roughly 311,000 miles on it. The truck still gets around 18.5 to 19.5 miles per gallon even with 2006 LTZ Surburban 20 x 8 tires and wheels.

My question, is there any partciular maintenance that should be performed on a great running truck with this kind of miles? What worries me most I suppose is thinks like the timing chain, cam shaft lobes and the like. Is there anything I need to keep an eye on to get a half a million miles out of this truck. The 2 door is a pleasure to drive as it rides nice a smooth and will turn on a dime. It has never given me any trouble and I simply want to take the best care of it. Thanks in advance.

**Tow Master** · 07-30-2008, 12:08 AM

Ya there are some things that will just go and they really arent a maintenance item. I know the motor will just go and go till it gets worn out! I have heard of the piston rings wearing so much the truck wouldnt start due to lack of pressure. I know the big things that go on them is the head gaskets, heads, and the cam shaft I can see going as well. I had the crank shaft crack in halph on mine

The one weird thing that went in mine is the oil pump driver. It connects the cam shaft to the oil pump and is located on the back of the motor where the distributor would be. Mine wore out and the gear spun instead of grabbing the cam shaft causing the oil pump to stop working! When I took it out the small drive shaft that connects the driver to the oil pump was also rounded as well. IIRC it was about $60 for the two peaces? My truck had 380,000 but the motor was replaced several times. With the mileage of your truck I think that is worth replacing!

CEB0217 · 07-30-2008, 12:28 AM

A 6.5 is gear drive doesnt have a chain i work at a wrecking yard and have seen a lot of cranks break and the same pump driver failure my brothers truck is having injector pump driver brain problms but we dont know why

**Tow Master** · 07-30-2008, 12:33 AM

Quote:

Originally Posted by CEB0217

A 6.5 is gear drive doesnt have a chain i work at a wrecking yard and have seen a lot of cranks break and the same pump driver failure my brothers truck is having injector pump driver brain problms but we dont know why

Really???!!!

I thought I was the only one!!

Pump driver brain? Like the PMD driver (little black box)?

CEB0217 · 07-30-2008, 01:46 PM

ya the little black box on the side of the pump but on my brothers it has been relocated to above the left valve cover for heat reasons

gtocato · 07-30-2008, 05:23 PM

I will replace the driver pieces at the next oil change. I appreciate all of ya'lls input. Just for info I read the infomation at Heath's diesel on how to check the health of an engine and the water tube test show that the engine is healthy. I have run Shell Rotella T 15-40 in the truck since it was new changing the oil ABOUT every 5 thousand miles.

When the truck was brand new it would not run right most of the time. It would run right and then without warning it would pour black smoke very heavily and would not make enough power to get above 30 miles an hour. I had to take it back to the dealer 7 time in the first year for this problem and I was within a gnats ass from turning it back in to the dealer under the lemon law. I am sure glad they got it fixed that last time at the dealer because it turned out to be the best truck I have ever owned. Never any problems above maintenance after that issue was repaired for over 300,000 miles.

Now the truck is like a part of the family! LOL

**Tow Master** · 07-30-2008, 11:55 PM

Wow glad you like it! It seems for some reasons 6.5's are touchy especially when trying to troubleshoot problems. But they are defiantly a reliable motor may not be the fastest but theres strong!

So what was wrong with the truck that they finally fixed?

gtocato · 08-01-2008, 05:35 PM

I am not sure what the cause was and I do not think they know either. They told me that they checked everything to do with the fuel -air mixtures and replaced the electrical components that could cause this problem. They kept it about a week that last time and I know that they had the passenger side dash out. But what they did I have no clue.

Alot of people have been telling me that my injectors have got to be worn out due to the miles on them. But they do not give any symptoms of not spraying properly. Any thoughts on that?

**Tow Master** · 08-02-2008, 12:59 AM

Its possible! But id say the injection pump would go bad before the injectors. Now that you say that have you ever replaced the "lift pump"? Its a inline pump thats under the cab. Have you ever replaced the injection pump as well?

Hmmm if you start to do all this upgrading it might be cheaper to upgrade to a dmax!

gtocato · 08-10-2008, 03:26 PM

I have replaced the lift pump several times. Live and learn, a gas lift pump does not last like the diesel models. I had the injector pump rebuilt at 200,000 miles because my dealer told me that I needed to. Before the injector pump rebuild, it cranked and it would run out fine but I had noticed that it did have a slightly lumpy idle. The rebuild smoothed her right back out.

The engine cranks, idles and runs out fine and I am looking for 500,000 total miles out of her. Do you think I should go ahead and replace the injectors?

I currently have two Duramax diesels in an 02 and 08 crew cab Siverados but the ole 6.5 is the most fun to drive around.