I have a GMC Yukon with the 5.3 and I just changed the plugs out. Its an 03 that came with Platinum's at 0.060 and I just put in Delco Iridiums at 0.40. Idles better and I'm wishful for any improvement to MPG's. So far I like them. Tune up was easy enough except the passenger side rear. Kind of a pain. Feel good after doing it myself and knowing its right and saved money!
First tune up I've done on my 5.3!
- Thread starter mcrn
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This is the next project for my truck. Its had a little bit of a rough idle since I bought it at 86k, so Im hoping this helps out a little bit. Congrats on doing it yourself! I was thinking about doing mine myself, but I think its a job better suited to someone with experience.
I had a 2004 Tahoe with the 5.3L engine. I drove it for 200,000 miles before trading it back in November. It was one of the best vehicles I ever owned. I had to have the transmission rebuilt, but the engine was bullet-proof.
My gas mileage, idle smoothness and engine response would improve every time I changed the plugs. I changed them at 75k and 150k with AC Delco Iridium. I had a plug wire go bad around 115k, so I replaced the entire set.
Congrats on doing it yourself. It is a great way to save a lot of $$ and you get up-close to your engine. Anyone can do it with time and patience.
My gas mileage, idle smoothness and engine response would improve every time I changed the plugs. I changed them at 75k and 150k with AC Delco Iridium. I had a plug wire go bad around 115k, so I replaced the entire set.
Congrats on doing it yourself. It is a great way to save a lot of $$ and you get up-close to your engine. Anyone can do it with time and patience.
Thanks guys. I agree anyone can do this! Having the right tools helped a lot. My neighbor is a mechanic and a friend so he let me borrow a couple tools to help with the back two. Mine had a little rough idle since I got it with 53K on it, especially with the A/C on. Its now just as smooth with the A/C on as off. Yes I tested it. Im in Florida! NewGuy what failed in the Tranny? Thats the part of this vehicle that worries me. I have Dex 6 in there now and hoping that helps. What was your fluid regimen on your tranny and why do you think it failed?
Originally Posted By: mcrn
I have a GMC Yukon with the 5.3 and I just changed the plugs out. Its an 03 that came with Platinum's at 0.060 and I just put in Delco Iridiums at 0.40. Idles better and I'm wishful for any improvement to MPG's. So far I like them. Tune up was easy enough except the passenger side rear. Kind of a pain. Feel good after doing it myself and knowing its right and saved money!
Good for you! Also you did right with the gap. Here is proof from GM:
xTooltipElement
Service Information 2003 Chevrolet Chevy K Silverado - 4WD | Sierra, Silverado (VIN C/K) Service Manual | Document ID: 2176126
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#03-06-04-060B: Information on New Spark Plugs and Gapping - (Jul 30, 2008)
Subject: Information on New Spark Plugs and Gapping
Models: 2004 Buick Rainier
2002-2004 Cadillac Escalade, Escalade EXT
2003-2004 Cadillac Escalade ESV
2004 Cadillac CTS-V
1997-2004 Chevrolet Corvette
1998-2002 Chevrolet Camaro
1999-2004 Chevrolet Silverado
2000-2004 Chevrolet Suburban, Tahoe
2002-2004 Chevrolet Avalanche
2003-2004 Chevrolet Express, SSR, TrailBlazer
1999-2004 GMC Sierra
2000-2004 GMC Yukon, Yukon XL
2001-2004 GMC Yukon Denali, Yukon XL Denali
2002-2004 GMC Sierra Denali
2003-2004 GMC Envoy XL
1998-2002 Pontiac Firebird
2004-2005 Pontiac GTO
2003-2004 HUMMER H2
with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4)
Attention: Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACDelco® Iridium Spark Plug Box. The statement will be removed from the boxes in the future.
--------------------------------------------------------------------------------
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard Corporate Bulletin Number 03-06-04-060A (Section 06 -- Engine/Propulsion System).
--------------------------------------------------------------------------------
• A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed.
• The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01 mm (0.040 in) when the spark plug is made.
Notice: The spark plug gap is set during manufacturing and should not be changed or damage to the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
© 2010 General Motors.
I have a GMC Yukon with the 5.3 and I just changed the plugs out. Its an 03 that came with Platinum's at 0.060 and I just put in Delco Iridiums at 0.40. Idles better and I'm wishful for any improvement to MPG's. So far I like them. Tune up was easy enough except the passenger side rear. Kind of a pain. Feel good after doing it myself and knowing its right and saved money!
Good for you! Also you did right with the gap. Here is proof from GM:
xTooltipElement
Service Information 2003 Chevrolet Chevy K Silverado - 4WD | Sierra, Silverado (VIN C/K) Service Manual | Document ID: 2176126
--------------------------------------------------------------------------------
#03-06-04-060B: Information on New Spark Plugs and Gapping - (Jul 30, 2008)
Subject: Information on New Spark Plugs and Gapping
Models: 2004 Buick Rainier
2002-2004 Cadillac Escalade, Escalade EXT
2003-2004 Cadillac Escalade ESV
2004 Cadillac CTS-V
1997-2004 Chevrolet Corvette
1998-2002 Chevrolet Camaro
1999-2004 Chevrolet Silverado
2000-2004 Chevrolet Suburban, Tahoe
2002-2004 Chevrolet Avalanche
2003-2004 Chevrolet Express, SSR, TrailBlazer
1999-2004 GMC Sierra
2000-2004 GMC Yukon, Yukon XL
2001-2004 GMC Yukon Denali, Yukon XL Denali
2002-2004 GMC Sierra Denali
2003-2004 GMC Envoy XL
1998-2002 Pontiac Firebird
2004-2005 Pontiac GTO
2003-2004 HUMMER H2
with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4)
Attention: Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACDelco® Iridium Spark Plug Box. The statement will be removed from the boxes in the future.
--------------------------------------------------------------------------------
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard Corporate Bulletin Number 03-06-04-060A (Section 06 -- Engine/Propulsion System).
--------------------------------------------------------------------------------
• A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed.
• The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01 mm (0.040 in) when the spark plug is made.
Notice: The spark plug gap is set during manufacturing and should not be changed or damage to the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
© 2010 General Motors.
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My transmission didn't actually fail and leave me stranded on side of the road, but it was getting difficult to shift between 2nd and 3rd. Especially when accelerating onto the interstate. I had the transmission fluid flushed every 40k miles, but it [censored] out around 140k miles. I took it to a local shop that repairs only transmissions. They told me that the internals were pretty worn and it was only a matter of time before it went out 100%. I had the tow package with transmission cooler as well.
If I had it to do over again I would have the pan dropped and the filter replaced every 40-50k miles. The local shop says it makes a huge difference to drop the pan and replace the filter vs. just doing a flush. I also pulled a trailer fairly often at highway speeeds. I am sure that didn't help.
Don't get me wrong. I drove that Tahoe all over the United States and almost took it to Alaska. It was the best vehicle I have ever owned. I would buy another one today if the gas mileage wasn't so bad. The transmission problem is the only issue and I don't think that is bad for 200k+ miles in all kinds of weather.
With respect to oil - I tried a little bit of everything and all kinds of OCIs. Havoline gave the best UOAs for dino, but I tried M1, Syntec, PP and others. I ran M1HM for the last year and it was terrific!!! I would recommend that oil to anyone with a big V8 and high miles. M1HM was very different in the engine vs. regular M1. Less noise and much smoother. I have a UOA from it that was just terrific. All wear numbers were single digits on a 9k OCI.
If I had it to do over again I would have the pan dropped and the filter replaced every 40-50k miles. The local shop says it makes a huge difference to drop the pan and replace the filter vs. just doing a flush. I also pulled a trailer fairly often at highway speeeds. I am sure that didn't help.
Don't get me wrong. I drove that Tahoe all over the United States and almost took it to Alaska. It was the best vehicle I have ever owned. I would buy another one today if the gas mileage wasn't so bad. The transmission problem is the only issue and I don't think that is bad for 200k+ miles in all kinds of weather.
With respect to oil - I tried a little bit of everything and all kinds of OCIs. Havoline gave the best UOAs for dino, but I tried M1, Syntec, PP and others. I ran M1HM for the last year and it was terrific!!! I would recommend that oil to anyone with a big V8 and high miles. M1HM was very different in the engine vs. regular M1. Less noise and much smoother. I have a UOA from it that was just terrific. All wear numbers were single digits on a 9k OCI.
mcrn - I am not trying to hijack your thread....but you might want to consider replacing the rear differential fluid around 90-100k miles. It comes with a synthetic fill from the factory, but after 100k miles it is pretty filthy. My Tahoe was a 2wd, so I didn't have all those gear boxes up front!! Thank Goodness!
One more things - Tires!! I got almost 100k miles out of a set of Michelin LTX M/S tires. Great in all kinds of weather. Just keep them inflated and rotated. A friend bought a less expensive set from Sears and had to buy 2 sets vs. my 1 set of Michelins. I think these are the best truck tires around. My Dad runs them on all his work vehicles.
I am laughing remembering what a PITA that rear passenger plug was for me too.
Good luck maintaining your Yukon. I am sure it is a great vehicle.
One more things - Tires!! I got almost 100k miles out of a set of Michelin LTX M/S tires. Great in all kinds of weather. Just keep them inflated and rotated. A friend bought a less expensive set from Sears and had to buy 2 sets vs. my 1 set of Michelins. I think these are the best truck tires around. My Dad runs them on all his work vehicles.
I am laughing remembering what a PITA that rear passenger plug was for me too.
Good luck maintaining your Yukon. I am sure it is a great vehicle.
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Thanks New Guy! Got the pan dropped with filter replacement when I bought it. Did the rear end at around 70K Front diff was rebuilt when I bought it. Mine is All wheel drive and the front diff has a drain plug and the rear doesnt! Makes no sense! When I bought it it came with those Michelin tires! Great tires! One reason I bought this vehicle over another I was looking at with some cheap no name tires. Read about a lot of people getting 100K out of those tires!
How is setting your plug gap too small 'right'?
Any new plugs will seem to help, with their clean and sharp edges.
But we want as wide of a gap as possible with no misfiring.
You did yourself a disservice by narrowing the gap. You went the wrong way. Put them up to at least the factory's recommendation. it fires more completely, esp at lean cruising speeds.
Any new plugs will seem to help, with their clean and sharp edges.
But we want as wide of a gap as possible with no misfiring.
You did yourself a disservice by narrowing the gap. You went the wrong way. Put them up to at least the factory's recommendation. it fires more completely, esp at lean cruising speeds.
Originally Posted By: mechtech2
How is setting your plug gap too small 'right'?
Any new plugs will seem to help, with their clean and sharp edges.
But we want as wide of a gap as possible with no misfiring.
You did yourself a disservice by narrowing the gap. You went the wrong way. Put them up to at least the factory's recommendation. it fires more completely, esp at lean cruising speeds.
I thought the same thing at first, but you'll see in my post earlier (you may have missed it) that he did the right thing...GM changed the plug recommendation and gap. TSB posted above.
How is setting your plug gap too small 'right'?
Any new plugs will seem to help, with their clean and sharp edges.
But we want as wide of a gap as possible with no misfiring.
You did yourself a disservice by narrowing the gap. You went the wrong way. Put them up to at least the factory's recommendation. it fires more completely, esp at lean cruising speeds.
I thought the same thing at first, but you'll see in my post earlier (you may have missed it) that he did the right thing...GM changed the plug recommendation and gap. TSB posted above.
50 years ago with lousy points ignitions we had .035" spark plug gaps.
Over the next decades, the industry worked itself up to .110" gaps.
Now with high energy ignitions, no points, and precious metal spark plugs, we are back to square one.
This shows a flaw in the ignition that narrowing the gap helps.
Over the next decades, the industry worked itself up to .110" gaps.
Now with high energy ignitions, no points, and precious metal spark plugs, we are back to square one.
This shows a flaw in the ignition that narrowing the gap helps.
Originally Posted By: mcrn
Tune up was easy enough except the passenger side rear. Kind of a pain.
If you want to know REAL "pain", try changing the plugs on a 4th gen f-body with an LS1!!
By the time I was done, my hands and arms looked like I went 20 rounds with a mountain lion and badger tag team!!!!
(I could have used that guy from the "small hands" Burger King commercial.
)
Tune up was easy enough except the passenger side rear. Kind of a pain.
If you want to know REAL "pain", try changing the plugs on a 4th gen f-body with an LS1!!
By the time I was done, my hands and arms looked like I went 20 rounds with a mountain lion and badger tag team!!!!
(I could have used that guy from the "small hands" Burger King commercial.
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