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OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 7:06 am
by Pantera
So, I'm debating on getting rid of my 2001 Suburban K2500 with the 6.0L because I can hardly make it from gas station to gas station (11 1/2 to 12 1/2 mpg hwy empty, 8 1/2 to 9 1/2 mpg hwy pulling my 4-place sled trailer) and wanted to know what people thought of the 1994-1999 Suburbans (or pickups) with the 6.5L Turbo Diesel.

BTW: I had a 1999 Suburban K1500 with the tried and true 350 V8 and got about 15-16 mpg hwy empty and 12-13 mpg hwy pulling the same trailer with the same sleds on the same route.

I'm not trying to race with the damn thing either, this is the whole family on board for the 300 miles one-way trip to the U.P. 4 times a season. I can't even make it there on a tank of gas with the 2001 where as the 1999 truck I could get there and be coming home before thinking about stopping for gas.

So I'm thinking on replacing it with the 6.5L powered Burban and want some feedback.

What kind of mileage can I expect?
How good is the power band?
How loud does that thing hammer?
How well does it start in the cold?
How reliable is the engine?
Do the trannies hold up behind that engine?
Would you definately want the 3/4 ton vs. the 1/2 ton due to the torque at the rear diff.?

P.S.: I've driven the big diesel trucks before I was even able to get my Class A CDL so I'm not bothered by the diesel smoke or smell. Just don't know anything about this particular engine.

Thanks a lot.
Pantera

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 9:45 am
by Coon
These trucks are great. I have a 98 Z71 Off Road 4X4 with the 6.5 Turbo in it. I have over 260,000 miles on it and still going strong. Watch the injection pumps on them at 180,000 and up they will need to be rebuilt. Did mine at 220,000 and did the turbo and glow plugs and new fuel filter at the same time even though they were ok. Put a high idle switch in it for warming up on those deep freeze morning starts- helps tremendously. Make sure that you keep the block heater plugged in at night or it won't. In your case you should be fine with the same as me- a 1/2 ton 4X4. or else get the 3/4 ton if you get just a 2 wheel drive. Tranny's are fine and so are the tranfer cases.

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 9:47 am
by RWL
even bad there twice as good as a ford or dodge......

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 9:49 am
by cromejob
I don't think your gonna get any better fuel mileage though. I pull my 4 place inclosed with my tahoe, and get between 9 and 10, my buddy this weekend pulled it with his 04 GMC diesel PU this weekend and only got 12 1/2, not bad, but he expected alot better.

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 9:59 am
by Coon
I get 23-28 empty and 17-20 loaded with my 1998 Chev 4X4 Z71 Off Road w/6.5L Turbo w/ 250 gallon utility diesel tank in the box.

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 10:13 am
by Wicks Viper
I don't have a chevy but my 6.0 diesel gets 17.5 to the gallon that's pulling my 2 sleds & one in the bed of the truck

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 10:35 am
by Thunder Cummins
Pantera, whatever you do don't buy a 6.5 turbo diesel they are the BIGGEST POS DIESEL MADE, TRUST ME!


For ultimate milage 22+ mpg 1994-1997 cummins 5 speed
Next would be a 1995-2002 PSD 5 speed 20+ mpg
New dodges get 19 mpg new fords get 17 new chevy/duramax gets 15.
Empty,give or take 1 mpg.

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 11:52 am
by catnfool
My dad had a 6.5 diesel and it has been a pain since he bought it. The motor went out at 160K, 5 speeds are aluminum cased in most, you have to take the turbo off to get at the glow plugs and injectors, and it only gets about 15mpg empty. The injector pump took a dump, along with the lift pump. If you want a diesel, get a real one = Cummins. My dad did and never looked back. btw, my 2000 5.3 gets 18-19 empty and about 13-15 pulling two sleds. the 6.0's are not much more power for the mpg sacrifice.

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 11th, 2005, 4:41 pm
by blizzardman
but you dodge guys seem to miss it here(HE WANTS A SUBURBAN)does dodge offer one,thats right i didn't think so,even ford offered an excursion diesel.the 6.5's are a light duty diesel as compared to the cummins and p-strokes.you can get them in 1/2 ton wereas ford and dodge is 3/4 up.they do have thier problems though i'll admit that,stay away from the 98-99's as they have oil spray pistons and are very prone to cracking in the main webbing,but they are the highest hp 6.5's.also gm extended the pump warrenty to 125,000 miles so if you do find one with less then that and have problems it will be replaced for free,but heres where the dealers will get ya they want to flush out the fuel tank and only they can do this(yeah right).heard of guys spending 600-800 bucks for the flush.free my butt.also the 94-95's use the obdI computer,you can check codes with a paperclip,whereas the 96 up needs a scan tool.also if the pump does totally give you fits the 94-95 can be converted back to mechanical pumps,also computer related if you want more power you can get a performance chip,whereas the 96 up you just reflash the computer.as for 1/2 or 3/4 ton there is very little difference between the 2 maybe 300-400 gvw,they even use the same 8 lug wheels.the 1/2's use a lighter rearend,without the floating axles ,and usually have better highway gears.and yes those turbo side g-plugs and inj's are hell.but you should only have to mess with them every 100-120,000 miles,if it's a 3/4 it will have the 4l80e trans which is very tough.i have a 94 with 4:10 gears and it pulls 20 mpg all day,with a good load it will drop to the 16 range.also you can get a wastegate controller to help in the power department.if your not gonna be pulling 7-10,000 lbs all day it should work just fine but if you are,definatly go cummins,if you do find a 98or 99 that you like at a gm dealer,make sure you get an engine warranty,the truck i have had an engine put in in 96 with 260,000 miles and the bill was 5500.00.i have had 6.2's and 6.5's for over 10 years and 600,000 miles and have yet to pull a head,you really need to maintain them keep the oil changed and keep clean fuel in it and change the fuel filter every 10,000 to 15,000 miles.if you want more info go to thedieselpage.com/ this is the 6.2/6.5 site.thedieselresource. is for dodge and thedieselstop. for ford.

OT: GM 6.5L Turbo Diesel: Good or Bad.....

PostPosted: January 12th, 2005, 12:53 am
by Thunder Cummins
[quote]but you dodge guys seem to miss it here(HE WANTS A SUBURBAN)does dodge offer one,thats right i didn't think so,even ford offered an excursion diesel.the 6.5's are a light duty diesel as compared to the cummins and p-strokes.you can get them in 1/2 ton wereas ford and dodge is 3/4 up.they do have thier problems though i'll admit that,stay away from the 98-99's as they have oil spray pistons and are very prone to cracking in the main webbing,but they are the highest hp 6.5's.also gm extended the pump warrenty to 125,000 miles so if you do find one with less then that and have problems it will be replaced for free,but heres where the dealers will get ya they want to flush out the fuel tank and only they can do this(yeah right).heard of guys spending 600-800 bucks for the flush.free my butt.also the 94-95's use the obdI computer,you can check codes with a paperclip,whereas the 96 up needs a scan tool.also if the pump does totally give you fits the 94-95 can be converted back to mechanical pumps,also computer related if you want more power you can get a performance chip,whereas the 96 up you just reflash the computer.as for 1/2 or 3/4 ton there is very little difference between the 2 maybe 300-400 gvw,they even use the same 8 lug wheels.the 1/2's use a lighter rearend,without the floating axles ,and usually have better highway gears.and yes those turbo side g-plugs and inj's are hell.but you should only have to mess with them every 100-120,000 miles,if it's a 3/4 it will have the 4l80e trans which is very tough.i have a 94 with 4:10 gears and it pulls 20 mpg all day,with a good load it will drop to the 16 range.also you can get a wastegate controller to help in the power department.if your not gonna be pulling 7-10,000 lbs all day it should work just fine but if you are,definatly go cummins,if you do find a 98or 99 that you like at a gm dealer,make sure you get an engine warranty,the truck i have had an engine put in in 96 with 260,000 miles and the bill was 5500.00.i have had 6.2's and 6.5's for over 10 years and 600,000 miles and have yet to pull a head,you really need to maintain them keep the oil changed and keep clean fuel in it and change the fuel filter every 10,000 to 15,000 miles.if you want more info go to thedieselpage.com/ this is the 6.2/6.5 site.thedieselresource. is for dodge and thedieselstop. for ford.[/quote]


He asked if a 6.5 TD is good or bad..........And the answer is bad.

If he is stuck in chevyland then too bad.If he wants a diesel powered SUV then he has to get an Excursion,best buy would be 7.3 PSD,stay away from the 6.0 no!