Time to buy a truck, I want a gmc diesel, I have questions please help!

[brentn]

Hey guys

It's time for a new truck and I would really really like a turbo diesel, I have heard that they are very reliable engines, with tons of torque in which I would like to get a trailer in the future to pull.

This truck would not be modded at all, I don't want to chip it or anything like that, I just want something reliable and smooth running with good driveability.

I have looked privately and diesels are expensive here, but there is one that falls in my price range and is in excellent condition.

It's a 2001 GMC sierra 2500 duramax diesel 4WD.

I did a little research and found that it uses an LB7 duramax engine which is known to have injector issues.

I really don't know much about turbo diesels, but I know that injectors for turbo's must support a high PSI. I looked around for a LB7 injector set and found a set of 8 with a price tag of 1700$, and a 500$ core charge. That's a lot of money, but at least I know what I'm getting myself possibly into.

Truck has 250000km's, that's about 155 000miles for you americanos. I looked for lower milage but I just can't afford it, too much money.

The owner claims that he has reciepts for a rebuilt transfer case and the allison transmission, so I figure if he can prove that I'm pretty much getting a new tranny and transfer case.

I will look for the usual suspects of high milage, bearings, u-joints, center bearing (if there is one) and ball joints, but I don't know what to look for in the engine.

What kind of quick tests or things should I look out for if I scout this truck out, or any other turbo diesel from GMC (01 or newer)?

Looking on youtube I saw some bad injector videos in which there was alot of idle hazing, but others with faulty injectors had no hazing... kinda confused me.

What do you guys think as well? Should I stay away? I am mechanically inclined and have read that to replace the injectors you must remove the valve covers and everything that blocks that path. There is a video of it on youtube (fast motion) that shows the job, and I could do it for sure. I've done head work before on my previous chevy, I can handle this.

Thing is, if I can see that there is an injector problem, I can use it as a bargaining chip and lower the price to pay for a replacement set.

Thanks alot for your time, you guys have helped me HUGE before with my truck and hopefully I'll get some informed opinions and advice this time too!!!

[brentn]

btw, I would love to own a dodge cummins, but their resale value is very high and just out of my price range... ?

[sniper_101]

I'm gonna have to recommend staying away from early Duramax trucks, especially with one that has over 200,000km. Yes some will be fine and problem free, but what are you willing to bet? I don't mean to sound rude here, but if you can't afford a later diesel, get a Gas Jobby. Most getting a diesel without much diesel experience don't realize the cost in maintenance, plus the cost of repair if/when something goes tits-up.

The GM 6.0 Vortec pulls strong . . . we have one as a fuel truck at the farm.

[Motolizard]

Bought my 1st diesel with little to no knowledge and it has been great for me. Some repairs can be spendy so get the Cummins 250,00 and I have only replaced the injection pump. Also get the 5.9 liter with the 6 speed manual bulletproof workhorse

[dirtbeater]

If you do go gas, go chevy and get an 8.1 L. MPG is a tad low ? but power is great.

[Rip Wheeler]

I was in the same boat, did loads of research, ended up getting a new Ram 2500 crew cab long box with a Cummins and the 6 spd manual. I bought mine new for 38K! Chevy was one of my options too, wasnt considering Ford (no particular reason, just not for me...) and I love this truck. Pulls like a Clysdale (actually, way better) just got back from some cabin work, pulled a enclosed trailer full of construction equipment over 3 mt passes, never even felt it. Kept it in 6th gear, 75 mph over the grades, more speed, just pushed on the go pedal. GONE!

The Duramax is a sweet combo, but their pricing new was way too high (new), couldnt touch one for 50K or less. But a good price on aused one is a great option. As you mentioned, I heard injector issues.

[brentn]

Well I really appreciate this info, and sniper you are not being rude, you're being truthful in a kind way. I really appreciate it!

I really want a diesel, not going to lie, but yes your right gas will get me lower KM's and a newer year for sure....

Either way, I want a 2500 gmc, so it'll probably be the 6.0L vortec if I go gas. I seem to find them for about 10000$ at about 150-200 000km's, usually near 200 000.

Has anyone tried auctions? Do you think it would be worth-while to go to a car auction, or is 10 000$ not going to really get me anything that the local classifieds can?

I just want a nice truck, that doesn't creak, squeek, and rattle when I drive it, like what I'm driving now. Money is about less than a month away, so I have some time to do research and ask you guys questions.

Any other opinions on the 01 diesel, let me know, still open to the idea but now I'm thinking gas just might be the way to go.

[Rip Wheeler]

Well I really appreciate this info, and sniper you are not being rude, you're being truthful in a kind way. I really appreciate it!

I really want a diesel, not going to lie, but yes your right gas will get me lower KM's and a newer year for sure....

Either way, I want a 2500 gmc, so it'll probably be the 6.0L vortec if I go gas. I seem to find them for about 10000$ at about 150-200 000km's, usually near 200 000.

Has anyone tried auctions? Do you think it would be worth-while to go to a car auction, or is 10 000$ not going to really get me anything that the local classifieds can?

I just want a nice truck, that doesn't creak, squeek, and rattle when I drive it, like what I'm driving now. Money is about less than a month away, so I have some time to do research and ask you guys questions.

Any other opinions on the 01 diesel, let me know, still open to the idea but now I'm thinking gas just might be the way to go.

Well, gas is fine, but if you want serious towing, than diesel is the only way to go. How often do you plan on towing? I can tell you my diesel gets decent mileage. I bet it will do as good or better than that 6.0 2500 but I have more room and way more power. Overall maintanance cost is higher on the diesel, and of course, fuel prices are about 40 cents more per gallon. If you plan on towing once a year, it may not be worth it.

[Motolizard]

Well, gas is fine, but if you want serious towing, than diesel is the only way to go. How often do you plan on towing? I can tell you my diesel gets decent mileage. I bet it will do as good or better than that 6.0 2500 but I have more room and way more power. Overall maintanance cost is higher on the diesel, and of course, fuel prices are about 40 cents more per gallon. If you plan on towing once a year, it may not be worth it.

My fuel mileage balances out the $.40. 1 ton dually 22 mpg @ 65-70 mph. Maintenance such as oil changes are done at twice the intervals, tires same, suspension same. Also diesel has at least 2-3 times the life of a gasser so the initial investment is higher but money is saved on fuel mileage and less oil changes. I sold my trailers and still drive my truck as a daily comuter. Refuse to buy a gas powered truck. I will never need more towing power than I have right now.

[redhurricane]

If you are reasonably mechanically inclined the LB7 is not really a bad powerplant. the injector job is not hard, just time consuming since you have to remove lots of things to get to them. Get over to dieselplace.com, great resource for duramax trucks. there's a DIY writeup on the injector swap with pics, too.

the allison is strong in that truck, swap fluid to Transynd synthetic and you'll never look back.

I have owned two LB7's, minor issues as with ANY used vehicle but I have been very happy. Upkeep is not really more than I would do to a gas truck, other than regular fuel filter changes. I change every other oil change, filter is usually about $35 or so. Sure, it takes 10 quarts of oil, but I also change about every 6-7k. 170000 miles on the most current rig and not a sign of performance loss.

[brentn]

I saw the injector replacement guide on that forum, tons of pictures and like you said, just lots of stuff to remove to get at them.

It looks to be a good 8 hours of work for sure if I take my time, nothing that I can't do on a saturday and have the truck ready for monday.

Did some more searching tonight and all the diesels are asking 14000$ and up for about 200 000km's, maybe a bit more. I did some more gas searching and found some real nice deals for 10 000$ but again I'm still torn on a diesel. If the owner can prove that the parts have been replaced and the injectors look to last another little bit, I might go for it as it's the only one in my price range.

Time will tell here, hopefully my money comes quick, and I can bring the check to the bank and have it cashed in 5 business days or less and go and buy something...

redhurricane, do you know if the 01 duramax has an easy access transmission pan? On my current truck I have to remove a tranny mount and lift the motor with the tranny to access one side of the pan. Problem is with my truck, is that the entire pan has to be dropped in order to change the fluid, not something that I like doing as it would probably spill all over the place.

Would be nice if the pan had a drain plug, or if not, at least is fully accessable in which I can easily unbolt it, drain the fluid and replace the filter.

Whenever I get a new truck I always go over everything, usually I buy beaters so I have to go over everything ?.

[dirtbeater]

Six in a row if you are going w/o spark plugs. 8.1 with spark plugs. At least drive one back toback with a 6.0.

[Kelso1]

I have an 02 lb7. Just rolled 205,000 miles. The only problem I have had is the fuel pressure regulator went out ($50 part but cost me 1100 cause the front of the truck has to be torn apart to get to it) and one alternator. I have a company truck so thankfully I only fill up about once every couple months. If I didn't have it I would get a gasser.

[2strokeDude]

The Duramax engine is awesome but the 01's are known for injector problems, which is usually why you can find them cheaper. I would try to find a newer Duramax. Also their allison trans is bullet proof. I know the owner of the local trans shop and he says he rarely gets a duramax in the shop. If you do have to opt for a gas though, the 6.0 will cover just about anyones towing needs.

[brad the best]

its funny you say the chevys have a lower resale than the dodges , i find it to be the other way around .

i paid half as much as your looking to spend on my 7.3 with less kilometers , 4x4 3500 long box 4 door .

[t_bois]

Regardless what you buy, get a manual trans. The only exception would be the Duramax. Automatics just don't hold up, most are replaced within the first 125,000 mi. and you usually get less than 1/2 that mileage from one that has been rebuilt.

Diesel is great for pulling heavy loads, but is difficult to start in cold weather and if you do a lot of short trips, the motor may never seem to warm up, which means worse MPG until it warms up.

I partial to Chevy when it comes to gas as they seem to have the best mileage per gallon. I own a 96 Ford diesel 4x4 F250 and only get 15 to 17 MPG (it's automatic which I hate)

[redhurricane]

redhurricane, do you know if the 01 duramax has an easy access transmission pan? On my current truck I have to remove a tranny mount and lift the motor with the tranny to access one side of the pan. Problem is with my truck, is that the entire pan has to be dropped in order to change the fluid, not something that I like doing as it would probably spill all over the place.

Would be nice if the pan had a drain plug, or if not, at least is fully accessable in which I can easily unbolt it, drain the fluid and replace the filter.

Whenever I get a new truck I always go over everything, usually I buy beaters so I have to go over everything ?.

the allison is completely accessible, with drain plug and external spin on filter. i did a write up on a transmission front seal replacement (look for a thread titled leak at bell housing at dieselplace).

Really overall I am very happy with the LB7 platform (which is 2001 to 2004.5) as a tow vehicle. As said above, if you're not really going to do serious towing, and have the cold to deal with, might want to consider gas over diesel. I am in the Denver area, we don't get as cold as you do here but still I am plugged in from about december to february if the temps are low enough.

If you keep your foot out of it, you can get fairly good mileage (I am averaging 16-18 in town right now)

[brentn]

Good to hear about the drain pan, drain bolt and screw on filter!! Never seen a tranny filter that screws on before, but then again I've only worked on a low-mid 90's chevy gas trucks.

How long do glow plugs last in these trucks?

Do you have to wait for the glow plug to get hot before you crank? (ignition left on for a few seconds or something?)

What kind of air filters are you guys running?

If you get an aftermarket exhaust, can the waste gate on the turbo handle the increased flow (ie, boost does not rise out of control)?

Any issues running an aftermarket exhaust and o2 sensors? I know on late model chevys I have heard that the check engine light will never go out if you get an aftermarket exhaust. Not to sure on the facts of that one, but again that's what I heard.

Also, why do these trucks have two alternators? Is it to run the fuel pump or something for the pressure that direct injection demands?

thanks for your time again, you guys are awesome!

[sniper_101]

Also their allison trans is bullet proof.

Lmao, yeah . . . right. When econo tunes push their limits that's far from "bullet proof". In stock form they hold up fine, but don't expect to throw any real power at it and hold up.

[2strokeDude]

Lmao, yeah . . . right. When econo tunes push their limits that's far from "bullet proof". In stock form they hold up fine, but don't expect to throw any real power at it and hold up.

I put a superchip in my old f350. 74,000 miles trans blown. thats with no towing, mostly highway miles. Took the superchip out, put a plow on 10,000 miles after the rebuild, then at 135,000 miles it blew again. My uncle has a duramax that he uses to tow his 45 foot race car trailer to virginia. 265,000 miles and the trans is like brand new.