Changing Oil question for the experts

I just recently purchased a 1996 GMC Sierra with 96,000 miles on the odometer. The truck is in beautiful shape both in the body and the interior, the engine looks well treated.

My question is about changing the engine oil, can anyone recommend what viscosity of oil I should use, straight or multiple and also what is the best oil filter? The truck and I are in Phoenix Arizona, so basically it's a high heat place.

Any advice would be greatly appreciated.

Rod Williams

Reply to
Rod Williams
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Well, go to your truck, pull out the user manual, and see what it says. If no user manual, I believe the top of your oil filler will say "Use only XX-XX oil". Use it.

Probably 10W-30, but could also be 5W-30 or something(they changed recommendations for oil weight in 96 or 97 I think).

Sam The truck and I are in Phoenix Arizona, so

Reply to
GaWd

use the viscosity on your oil filler cap and use a WIX made filter (i.e. any of NAPA's, or a WIX branded one). your owner's manual will give you a chart of acceptable oils and temperature ranges. being in AZ, you'll probably want to run towards the heavier side (10w30 vs. 5w30).

HTH, Bret

Reply to
Bret Chase

I don't see any advantage of 10W30 over 5W30 in hot climates. Both are the same viscosity when hot. And both are thicker than that when below operating temperature. However, I believe in the use of synthetic in hot climates, especially if you are going to be working the engine hard.

Reply to
Dick

actually, the 10w30 will hold up better in the heat as the base oil is thicker (10w vs. 5w) so they can use less additives to get to a hot 30w. synthetics may be nice, but I personally can't justify the cost (5 bucks a qt for Mobil 1 vs. 1.07 a qt for reg. Mobil).

-Bret

Reply to
Bret Chase

Another plus for synthetics. They don't need VI improvers because they do not thin as much when they get hot. Personally I think the added cost of using synthetic is minor compared to the cost of the vehicle. But I work my vehicles hard pulling heavy trailers.

Reply to
Dick

10W - 30 Synthetic is the way to go in this heat. You will see a difference in you oild presure reading when the motor is good and hot. Don't waste your money on five quarts on 5W - 30 in this heat. Been there! I use AC oil filters based on the information contained in "filter study" located at
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Wix andWix/NAPA are a good bet as well. I bought a 98 Sonoma 2.2L with 105K on the odometer last year. The owner switched over to Valovoline Max Life at 65K. It now has 125K and has had a steady diet of Mobil 1 10W-30 since 105K. I use a 5K oil change interval. This truck travels from Kingman, AZ to Laughlin, NV and back 5 days per week. The daily trip from Laughlin up through the pass is no walk in the park, especially for the little 4 cylinder. ( 120 degrees today ) Truck is running well and used no oil between changes.

Our WalMart in Kingman has the 5 quart jugs of Mobil 1 as well. Save sa couple of bucks.

Hope this helps.

Paul

Reply to
theBun

The oil filter study is interesting. Thanks for the link.

HMc

Reply to
Howard McCollister

Just always use Mobil 1 oil and filters, that's what I use. You MAY pay more, but you can't rest assured that there isn't anything better that you can use, and with this oil you can stretch your oil changes out to at least

5k or more... Check here for an on going study of Mobil 1
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Reply to
Troy

Reply to
sidewinder

Thanks to all who replied. In the early seventies I was a VW line mechanic and engine rebuilder, worked at a dealership for a while so I know about changing oil but a friend said I should run straight 40 weight oil in the vehicle since it had 96,000 miles. The vehicle doesn't smoke, leak or appear to use oil for the past 60 days that we have had it and what my friend said didn't make sense to me so that is why I made the post. Also I was curious about a good make of oil filter and that was answered well. Since there is a long delay to when a message is posted, I changed oil before any of the replies came in because I needed to. I used Castrol 10w 30 oil with a Fram oil filter. I marked my calander for the next change at which time I will buy a NAPA gold filter or Wix and consider synthetic oil of the same weight.

Thanks again, first pickup I ever owned and the first GM product with the exception of my first vehicle, a 1950 Chevy automobile, automatic transmission (first year for automatic), purchased in 1957.

Reply to
Rod Williams

straight 40 weight? good lord, talk about some clacking lifters....

-Bret

Reply to
Bret Chase

please explaine how straight 40 = clacking lifters

and, as Grandpa used to say, 'this better be good'............

Reply to
Gary Glaenzer

because the engine was designed to run 5W30 oil, running such a significanty heavier oil such as SAE40 will cause lack of lube problems. the oil passages' and bearings' oil clearances were never sized nor intended for such a thick oil esp at start up. the oil is just too thick. my owner's manual for my 88, which is spec'd 10w30, (IIRC) specs a min temp of around

50 degs to use SAE 30, even in AZ it can get below that. now we're talking about a '98 which has tighter clearances for 5w30 and SAE40 which doesn't appear on GM's chart.

YMMV, Bret

Reply to
Bret Chase

The best choice in any case is straight 30W. A good name brand will help. I wouldn't pour multi-viscosity oil on the friggin ground.

Reply to
Steve Barker

Straight 40 won't make the lifters rattle. Why would it? All oil is basically thicker when cold. I've run straight 50W in a 400 ford and never heard a lifter rattle. OH and yes it was all year around in kansas.

Reply to
Steve Barker

Wrong. The engine was not "designed" to run any particular type of oil. They only recommend the junky multi-viscosity oils to meet mileage ratings.

Reply to
Steve Barker

We have 3 where I work pushing 300,000 on good old Mobil straight 30W changed every 3,000. Synthetics will not improve on this. (OR anythin else for that matter)

Reply to
Steve Barker

"Bret Chase" wrote

significanty

Unfortunately, Bret....this is all a bunch of horseshit...to put it mildly. I bet you don't even know what the main bearing clearances are on modern motors, and if they have changed from say...20-30 years ago? I'll give you a hint....they haven't changed. I've run oil that is intended for diesels in my own vehicles that are spec'd out at 5/30 oil. Nothing happens...no lifter noise...nothing. Oil passages don't get blocked up, bearings don't fail because their clearances are only intended for 5/30 (or at least you say).

Yes, it's best to just run what the manufacturer recommends. No doubt about it. But the sky is not going to fall if you put in some heavier viscosity oil, contrary to what some of the "chicken littles" around here say.

Ian

Reply to
shiden_kai

Well! It is NOT bad advise. Multi-viscosity oil is the Bad advise. So there!

Reply to
Steve Barker

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