Opinions? 6.5 TD......

What are the opinions on the 6.5? I'm debating whether to look at them for the next truck. either a Suburban or ext. cab truck. Was this optionable in a 3/4ton 4x4? What years were the 6.5 in and which auto backed it up (4L80?

4L80-E) Thats what I'd be looking at, Thanks.
Reply to
Demon
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The 6.5's started somewhere in the early '90's I believe. There are many versions that people consider better, the latter (97-99 in pu's '97-03 in vans) ones are supposedly the best due several reasons, one is thier large dual-wide thermostat housing (more coolant flow, I guess the single-wide ones had problems with cooling under heavy load..)...among others...there are several other small changes..I can't remember what they are As far as transmissions go, I stay away from autos...so I can't help there, my NV4500 manual is working great though at 175,000mi (1 clutch at 135,000mi..$300), the engine is doing very well as well I don't pretend to be a diesel mechanic, but good diesel mechanic I know told me, among other things, that one of the biggest reasons he sees in failure in this engine is people's lack of changing the Fuel Filter. He reccommended every 10,000mi. I've rebuilt and messed with my share of SBC's, and I know most people don't change or negelect thier fuel filters on those, but don't do that with this engine. Of course, I should not fail to mention the crappy standyne injection pump they put on these things until the '99 or so, a large majority of them have failed, but luckily enough for most owners they fail almost always before the 100,000mi warranty runs out so the dealers ended up replacing most of them with a new improved design. I've heard some people say it's just the elec. controller mounted to the outside of the pump...I really don't know..but I would ensure that the pump has been replaced/repaired if it's a '98 or under.. BTW, perhaps it's not neccessary, but I run Mobil 1 Delvac in it with a Mobil 1 filter, and change the oil every 6,000mi...

BlazerMan

Demon wrote:

Reply to
73blazer

I have heard of the "bad" pumps on them but I never really knew the scoop. I'm an apprentice heavy duty mechanic so I'm more than a little familiar with diesels but I only work on industrial stuff and highway tractors. But if the pump is the only fatal flaw, that's not too bad. Anyone else?

Reply to
Demon

Yes, I will pipe in here. The '92-'93 6.5 TD were mechanical injection engines. In '94, they went to an electronic injection pump. The pump is made by one of the best in the business, Stanadyne, but the FSD (fuel soleonoid driver) or PMD (pump mounted driver) is an electronic device in a poor location. I've spoken with Stanadyne about this design and they claim there is no issue. They, however, are not going to admit there is a poor design because it would cost them millions of dollars to remedy the issue. Many guys have made heat sinks and relocated the PMD to different places. Many have relocated the driver out of the engine compartment and have never failed one. The last guy I spoke with about this said his PMD was installed in '94 and has been on three different trucks - same part. His is remotely installed on the skid plate and has never been too hot to touch. The issue is not the pump; the issue is with the hot PMD that needs a new home.

In '97, they made several cooling upgrades to address overheating issues. This is the high volume water pump, dual thermostat and a couple other frilly things. This was to try to cover up a crappy design on the fan clutch. I've spoken with many folks that claim they did the cooling upgrades on their older models and saw no significant difference. Again, the fan clutch is a piss-poor part and many are already trash out of the box. Replace this with a HD aftermarket unit and heating problems should go away (assuming clean rad., coolant, OEM t-stat, etc.).

In '97 or '98, they made a couple other changes with more iron around the main cap bolts and oil spray for cooling cylinders.

The electronic injected motors are sleeping giants in that they are wimpy with factory settings. Get your hands on a performance chip, turbo controller and a couple other small items and you're real close to the power of a factory Duramax, believe it or not. I thought I had made a mistake with buying my '95 because the previous '92 I had driven was so much stronger. Then I got my hands on a Max-E-Torque chip and Turbo-Master and about had a cupcake the first time I drove it. It was I put in a whole different engine. We've got three of these in our family ('92, '95, '96) and they're all good motors. A buddy of mine has a '93 with 420,000 miles on the clock and the engine has NEVER been apart (that was not an error in typing).

You should expect to replace the inj. pump in 100,000-150,000 miles. That is normal, though. Not much lasts forever. Good pump, from what I understand - just needs to have the PMD in another place.

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has tons of information and the guys there are helpful. there is another site, too, that is helpful, but it's a pay membership.

Snowman

Reply to
Snowman

Thanks, helpful information.

Reply to
Demon

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