a 170k 3/4 ton with 2wd and 4.10 diff. According to the owner, it runs good except sometimes on hills it loses power, doesn't stall, just loses power but a dose of fuel additive takes care of that problem. Now, I know nothing about the 6.5td except what I've read on this forum but that sounds middling strange to me. Is it possible and, if so, what is the likely culprit?

Vin check (thanks again) show last work done on this vehicle was fuel pump replacement at 74k and ip replacement at 87k. Big blank from there to 170k. Does carfax contain info from other sources than dealerships? Really curious about that missing 80k. Thanks

Peyton

"Vin check (thanks again) show last work done on this vehicle was fuel pump replacement at 74k and ip replacement at 87k. Big blank from there to 170k. Does carfax contain info from other sources than dealerships? Really curious about that missing 80k. Thanks"



I think VIN check may only show warrantee work at dealer and not maintainance.

a 170k 3/4 ton with 2wd and 4.10 diff. According to the owner, it runs good except sometimes on hills it loses power, doesn't stall, just loses power but a dose of fuel additive takes care of that problem. Now, I know nothing about the 6.5td except what I've read on this forum but that sounds middling strange to me. Is it possible and, if so, what is the likely culprit?

Vin check (thanks again) show last work done on this vehicle was fuel pump replacement at 74k and ip replacement at 87k. Big blank from there to 170k. Does carfax contain info from other sources than dealerships? Really curious about that missing 80k. Thanks

Peyton

I agree - I don't see how a quick shot of additive is going to make it better. Besides, if it were true, why wouldn't he be running it all the time?

I would suspect something's wrong with the turbo system. But at this point, I'm just guessing and going with the most likely culprit. When you're hard on the throttle, you should only get a light gray haze of smoke - at the most. You might, initially, get a quick burst of black.

VIN check only shows what was reported within the GM system, CarFax will only show if major work was done and reported, if an independent, or owner did the work and work wasn't documented in a 'official system" ie dealer or Ins. Co, it won't show up.

I agree - I don't see how a quick shot of additive is going to make it better. Besides, if it were true, why wouldn't he be running it all the time?

I would suspect something's wrong with the turbo system. But at this point, I'm just guessing and going with the most likely culprit. When you're hard on the throttle, you should only get a light gray haze of smoke - at the most. You might, initially, get a quick burst of black.

Thanks, sounded wrong to me ... more info needed! ... hopefully today or tomorrow. Maybe the lack of power just isn't noticeable when driving normally (i.e. a light foot) on level roads. Does this sound somewhat like a wastegate problem?

VIN check only shows what was reported within the GM system, CarFax will only show if major work was done and reported, if an independent, or owner did the work and work wasn't documented in a 'official system" ie dealer or Ins. Co, it won't show up.

Thanks, I was afraid that was how it worked. I didn't want to pay CarFax if it just regurgitated the GM system info.

Peyton

Does it turn on the check engine light when it loses power?

Does it make black smoke under power? It should make a puff when you hit the gas and clear up after that.

Also, do the lift pump test.

On my 6.2s, the ip would need to be overhauled every 100k miles. At 150k miles, they would loose a lot of power on hills due to the worn ip.

Does it turn on the check engine light when it loses power?

Does it make black smoke under power? It should make a puff when you hit the gas and clear up after that.

Don't know, I'll ask about that. Looking at it tomorrow.

Also, do the lift pump test.

On the todo list for tomorrow.

On my 6.2s, the ip would need to be overhauled every 100k miles. At 150k miles, they would loose a lot of power on hills due to the worn ip.

It was replaced at 87k, so it's coming up on 90k now. Something to think about.

Thanks guys,

Peyton

What did you think of the truck? I'm interested if it does not work out for you.

I finally got a chance to do a preliminary check on the 99 3/4 ton suburban Friday. Two problems: SES light on and turbo wastegate not operating ... no vacuum at wastegate. I am going back tomorrow with vacuum gauge and scanner (if I can rent one at O'Reilly's or Autozone) for more thorough check out. Will check pmd location and do a lift pump test as well.

Otherwise, it started easily with no smoke, idled smoothly at about 700 rpm or so, passed the CDR test (pulled about 3-1/2" at 1500rpm), rad hose didn't get hard on startup and there was no puffing or strange noises from the oil filler tube,

Peyton

Sounds like it may have a bad wastegate solenoid. If that is the case, that is an easy fix by just changing the solenoid. It is a 99, so less chance for the vacuum pump to be bad.

Well, i just got a call ... looks like it's been sold out from under me. Thanks for all the help guys.

Peyton

Well I guess its all the better for me too. A road trip to Houston from Oregon to look at a truck would not have made the spouse happy.