I just bought a 8.1L Suburban. 2003 4x4 model with 4.10 gears, 134k miles. I will primarily use it to tow my travel trailer and will get little to no use this winter. I've tried searching for a UOA anywhere on the internet and here too of course with nothing found. I use Rotella T6 in my wagon with good results and would consider that. It calls for 5w30 of course being a GM. I saw someone else a few years ago was using T6 and switched to Redline 0w30 and found the start up tick was mostly eliminated. Mine has the tick which goes away within a minute. I have no idea what oil is in it but it looks pretty fresh and I have records of regular oil changes over the last couple of years but don't know when the last change was. Should I change it now, wait till spring, any suggestions on what to use? Front crank seal was just replaced and it is not currently leaking any oil.
8.1L Suburban
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An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
T6 is excellent oil, but is a 5W40.
T6 is excellent oil, but is a 5W40.
Originally Posted By: Donald
An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
T6 is excellent oil, but is a 5W40.
When towing, sometimes the bigger engines don't burn any more gas than a smaller one as they can often run in a higher gear and aren't seeing WOT as much. It's just the unloaded mpg that sucks.
An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
T6 is excellent oil, but is a 5W40.
When towing, sometimes the bigger engines don't burn any more gas than a smaller one as they can often run in a higher gear and aren't seeing WOT as much. It's just the unloaded mpg that sucks.
Perfect example - ford 6.8s in 3/4 and 1 ton trucks would get BETTER mileage towing than the 5.4
I have a friend who is meticulous about his vehicles and he the 2004 or 2005 version of this same Suburban. He loves it. I love driving it too!! The thing is a stump pulling monster!!
Anyway, he owned the truck since new and ran the 5w30 in it for awhile. Then a few years ago, he started running M1 0w40 in it.
Now he runs a 50/50 mix of M1 0w40 and M1 5w50 in it. The 5w50 is really a heavy 40 weight. And the 0w40 is a real light 40 weight. Both oils have OUTSTANDING additive packages and well documented performance.
Anyway, he owned the truck since new and ran the 5w30 in it for awhile. Then a few years ago, he started running M1 0w40 in it.
Now he runs a 50/50 mix of M1 0w40 and M1 5w50 in it. The 5w50 is really a heavy 40 weight. And the 0w40 is a real light 40 weight. Both oils have OUTSTANDING additive packages and well documented performance.
If you ever need to buy a radiator for it you must go to the dealer to buy it. the dealer one is about $800. the aftermarket radiators do not fit I have been there done that more than once with those 8.1 liter trucks
Originally Posted By: Phishin
I have a friend who is meticulous about his vehicles and he the 2004 or 2005 version of this same Suburban. He loves it. I love driving it too!! The thing is a stump pulling monster!!
Anyway, he owned the truck since new and ran the 5w30 in it for awhile. Then a few years ago, he started running M1 0w40 in it.
Now he runs a 50/50 mix of M1 0w40 and M1 5w50 in it. The 5w50 is really a heavy 40 weight. And the 0w40 is a real light 40 weight. Both oils have OUTSTANDING additive packages and well documented performance.
Sorry but the BITOG'r in me had to comment. It is not a 40w oil but rather a light 50w oil.
I have a friend who is meticulous about his vehicles and he the 2004 or 2005 version of this same Suburban. He loves it. I love driving it too!! The thing is a stump pulling monster!!
Anyway, he owned the truck since new and ran the 5w30 in it for awhile. Then a few years ago, he started running M1 0w40 in it.
Now he runs a 50/50 mix of M1 0w40 and M1 5w50 in it. The 5w50 is really a heavy 40 weight. And the 0w40 is a real light 40 weight. Both oils have OUTSTANDING additive packages and well documented performance.
Sorry but the BITOG'r in me had to comment. It is not a 40w oil but rather a light 50w oil.
JHZR2
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if youre primarily towing over long distances, it really seems to me that going with the 5w-40 is a good move. i wouldnt hesitate using it.
I have a 7.4L Suburban, also 4.10 gear - used it to haul a 12,000 lb enclosed race car trailer. I always used M1 15W-50 when towing and never had any problems. Make sure you tow in 3rd gear, not high gear with lockup. Big block Chevys like to spin, it was no problem turning 2500-3000 RPM steady on the highway. IIRC I got around 9-10 mpg towing. The M1 0W-40 might also work, I would consider the 5w30 marginal for heavy long distance towing in the summer.
How do you like it? I have a '97 heavy 3/4 ton with a 5.7 & 4l80e in it, and I'm back and forth between wanting to put a 6.0 in it, or a 454/8100. Any thoughts? The 8100's apparently are known for some kind of piston issues apparently?? I recently swapped a 1-ton full-floating 4.10 into it too. It's mostly a work truck.
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So far I love the Suburban, but have not had it long enough to tow with it. I've been spending some time getting some stuff fixed that needed it.
I have considered M1 0W-40, T6 or PU 5w30. These days any of them are readily available at Walmart or Meijer near me at reasonable prices.
It does get pretty crummy fuel economy solo. It needed plugs/wires bad and was missing at times when I drove it back from Knoxville, TN where I bought it and got 12.6 mpg driving with the faster traffic. My next 400 miles I calculated 12.1 which was a combination of the rest of that trip plus some local driving. I only got 8-9 most of the time pulling my trailer with my wagon and I figure this will do just as well. With the 4.10 gears in the Suburban and the 2.93 gears in the wagon the Suburban will be running the same rpm's in OD as the wagon was in 3rd. With tow/haul mode it is fine to run in OD as long as it isn't shifting too much.
Thanks for the advise, I'm leaning towards something thicker like the T6.
I have considered M1 0W-40, T6 or PU 5w30. These days any of them are readily available at Walmart or Meijer near me at reasonable prices.
It does get pretty crummy fuel economy solo. It needed plugs/wires bad and was missing at times when I drove it back from Knoxville, TN where I bought it and got 12.6 mpg driving with the faster traffic. My next 400 miles I calculated 12.1 which was a combination of the rest of that trip plus some local driving. I only got 8-9 most of the time pulling my trailer with my wagon and I figure this will do just as well. With the 4.10 gears in the Suburban and the 2.93 gears in the wagon the Suburban will be running the same rpm's in OD as the wagon was in 3rd. With tow/haul mode it is fine to run in OD as long as it isn't shifting too much.
Thanks for the advise, I'm leaning towards something thicker like the T6.
M1 HM 5w30 is a tad thicker at 100C but still in the proper grade for your engine. Also loaded with additives that will be good for your engine including seal conditioners.
T6 and 0w40 are sort of thick at 100C but would work just fine. I would lean on a synthetic 5w30 though to squeeze the most out of your mpg.
T6 and 0w40 are sort of thick at 100C but would work just fine. I would lean on a synthetic 5w30 though to squeeze the most out of your mpg.
Originally Posted By: Donald
An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
Seriously, I think your truck killed Jesus.
An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
Seriously, I think your truck killed Jesus.
I'd try M1 0W40.
Originally Posted By: 901Memphis
M1 HM 5w30 is a tad thicker at 100C but still in the proper grade for your engine. Also loaded with additives that will be good for your engine including seal conditioners.
T6 and 0w40 are sort of thick at 100C but would work just fine. I would lean on a synthetic 5w30 though to squeeze the most out of your mpg.
I had considered the M1 HM 5w30 as well, I forgot about that. Possibly a good option. I think I'm still leaking towards T6 or M1 0W-40. The thicker oil had no impact that I could tell on the mpg in my wagon compared to 5w30 oils. Big slow turning engines are less impacted by oil viscosity I believe. I'm definitely going with a synthetic and hoping I don't put enough miles on it to worry about changing the oil more than once a year. I've been happily using M1 oil filters in my other cars and plan to stick with them for this vehicle as well.
Change it now or wait till spring? I don't plan to drive it much at all this winter. I have no idea what oil is in it.
Originally Posted By: AHC
Originally Posted By: Donald
An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
Seriously, I think your truck killed Jesus.
Seriously?
M1 HM 5w30 is a tad thicker at 100C but still in the proper grade for your engine. Also loaded with additives that will be good for your engine including seal conditioners.
T6 and 0w40 are sort of thick at 100C but would work just fine. I would lean on a synthetic 5w30 though to squeeze the most out of your mpg.
I had considered the M1 HM 5w30 as well, I forgot about that. Possibly a good option. I think I'm still leaking towards T6 or M1 0W-40. The thicker oil had no impact that I could tell on the mpg in my wagon compared to 5w30 oils. Big slow turning engines are less impacted by oil viscosity I believe. I'm definitely going with a synthetic and hoping I don't put enough miles on it to worry about changing the oil more than once a year. I've been happily using M1 oil filters in my other cars and plan to stick with them for this vehicle as well.
Change it now or wait till spring? I don't plan to drive it much at all this winter. I have no idea what oil is in it.
Originally Posted By: AHC
Originally Posted By: Donald
An 8.1L engine, you have got to be kidding me. How can you tow a travel trailer when it will need to tow a gas tanker behind it?
Seriously, I think your truck killed Jesus.
Seriously?
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You are going to have to change your user name, now that you have truck.
My vote: "finallyhaveatrucklovinit"
My vote: "finallyhaveatrucklovinit"
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Originally Posted By: caravanmike
You are going to have to change your user name, now that you have truck.
My vote: "finallyhaveatrucklovinit"
You're right! I didn't think of that. I at least need to change my signature.
You are going to have to change your user name, now that you have truck.
My vote: "finallyhaveatrucklovinit"
You're right! I didn't think of that. I at least need to change my signature.
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