When Is A Good Time To Switch To Synthetic?

sage55 · October 9, 2008

I recently purchased an 04 GMC Sierra 1500 Z71 Ext cab with 21,000 miles on it. From reading in the manual none of the fluids are due to be changed for a while now and the oil isn't due until 24,000 miles.

Would it be to soon to switch my motor oil to synthetic at 24,000 miles?

Majorleaguebass · October 9, 2008

Well 1st off welcome...and 2nd i would switch to syn. oil at your next oil change, i just changed all my fluids to syn. at 77,000 miles. If you have the extra money, i would just go ahead and do it. That is my opinion, iam sure someone else will also let you know theirs.

merlin5577 · October 9, 2008

I recently purchased an 04 GMC Sierra 1500 Z71 Ext cab with 21,000 miles on it. From reading in the manual none of the fluids are due to be changed for a while now and the oil isn't due until 24,000 miles.

Would it be to soon to switch my motor oil to synthetic at 24,000 miles?

Go for it. 24,000 miles is plenty for all the wear patterns to set. You should be good to go. Welcome to the site BTW!!! We need pictures!

sage55 · October 9, 2008

Thanks for the welcome guys and the advice. Next oil change I'll switch over to synthetic then. I'll try to get pictures of the truck tonight.

spiritrider1100 · October 10, 2008

Most people go with anything over 6000 miles Go for it its good stuff

The Factory Man · October 18, 2008

I recently purchased an 04 GMC Sierra 1500 Z71 Ext cab with 21,000 miles on it. From reading in the manual none of the fluids are due to be changed for a while now and the oil isn't due until 24,000 miles.

Would it be to soon to switch my motor oil to synthetic at 24,000 miles?

Does the fact that millions of engines from various manufacturers come with synthetic engine oil from the factory give you any hint at the answer to your question?

BlazerHelper · October 19, 2008

Given that you have purchased a used auto, I'd try to stick with what was run from the factory. Every different oil company that sells oil at your local autoparts store uses a different formula. Pick one and stick with it. Since you drive a GM, I'd run a GM authorized oil. I know I'll get lots of flack for saying this, but I'd stay away from Quaker State and Pennzoil. Instead of going to synthetic, I'd change the oil every 3K miles with what the owner's manual says. Run only AC/Delco oil filters.

I'm a Ford guy and I only run semi/synthetic Motorcraft Oil and Filter in my 2003 Escape and 2004 FX4. I have a 1987 Mustang GT with over 300K on it and changed the oil every 3K miles and runs like new. If you do a search online for the 'Oil Filter Study' you'll find that the AC/Delco and Motorcraft filters are just re-boxed versions of the Puroilator Pure 1 filters. Can't get better than that unless you buy Mobil1 Oil Filters.

ALange · October 19, 2008

Synthetic oil should be fine after the engine break in. I would change it immediately.

The Factory Man · October 19, 2008

Synthetic oil should be fine after the engine break in. I would change it immediately.

Perhaps you missed the point I was trying to make in my previous comment. Millions of engines break-in just fine on synthetic engine oil. General Motors has run hundreds and hundreds of engines on dynomometer durability cycles and not one failed to break-in. Break-in on todays engines is practicly a non-issue because of the precision machining and assembly that takes place. I have never seen a General Motors engine that had a problem because it didn't break-in properly due to synthetic oil. To suggest that synthetic oil prevents proper break-in is just passing on bad information. Every Cadillac engine built today is filled with synthetic engine oil. These engines are not built any differant because they are filled Mobil 1 at the assembly plant.

dlstewart01 · October 19, 2008

Given that you have purchased a used auto, I'd try to stick with what was run from the factory. Every different oil company that sells oil at your local autoparts store uses a different formula. Pick one and stick with it. Since you drive a GM, I'd run a GM authorized oil. I know I'll get lots of flack for saying this, but I'd stay away from Quaker State and Pennzoil. Instead of going to synthetic, I'd change the oil every 3K miles with what the owner's manual says. Run only AC/Delco oil filters.

I'm a Ford guy and I only run semi/synthetic Motorcraft Oil and Filter in my 2003 Escape and 2004 FX4. I have a 1987 Mustang GT with over 300K on it and changed the oil every 3K miles and runs like new. If you do a search online for the 'Oil Filter Study' you'll find that the AC/Delco and Motorcraft filters are just re-boxed versions of the Puroilator Pure 1 filters. Can't get better than that unless you buy Mobil1 Oil Filters.

I believe that Champion Labs make most of AC Delco filters as well as Mobil 1 filters while Purolater (Arvin Meritor) makes Motorcraft filters.

The approved GM oil list can be found here: http://www.hollonoil.com/GM6094MRegisteredProducts.pdf

For synthetic try GM4718M

Also Quaker State and Pennzoil are owned by Shell and are COMPLETLY different formulas than they were 30 years ago.

(Pennzoil is the best selling dino oil on the market)

Have a good one,

Don

merlin5577 · October 19, 2008

Synthetic oil should be fine after the engine break in. I would change it immediately.

Beautiful truck Hawghauler! You should create a new member thread and post more pictures! Welcome to the site!

Zembonez · October 19, 2008

I switched at 1000 miles. No issues at all.

Outbacker · October 19, 2008

As soon as I hit 1000 km's, I switched to Mobil 1. I also plan to do the tranny soon, changing it to syn oil. And someday, the rear end will be changed out as well. I plan on keeping this truck for a long time, and I figure that switching over now will be the first step to keeping it forever.

Cheers.

Z45 · October 23, 2008

Perhaps you missed the point I was trying to make in my previous comment. Millions of engines break-in just fine on synthetic engine oil. General Motors has run hundreds and hundreds of engines on dynomometer durability cycles and not one failed to break-in. Break-in on todays engines is practicly a non-issue because of the precision machining and assembly that takes place. I have never seen a General Motors engine that had a problem because it didn't break-in properly due to synthetic oil. To suggest that synthetic oil prevents proper break-in is just passing on bad information. Every Cadillac engine built today is filled with synthetic engine oil. These engines are not built any differant because they are filled Mobil 1 at the assembly plant.

My 2005 CTS came with synthetic oil. It has never used any oil in its 30,000 mile of existence. I ran it the first year on the oem Mobil 1 (approx. 9,000 miles) but have used Amsoil every year since. About due for my my 4th oil change in Nov. I have never seen the OLM light come yet but I still change it every fall no matter the miles. Miles mean nothing me with synthetic oil in there. Have used synthetic oil for many years and consider everything else 2nd best.

I changed my 2008 GMC over to synthetic at about 1,000 miles. The engine, trans and both differentials.

The Factory Man · October 24, 2008

Perhaps you missed the point I was trying to make in my previous comment. Millions of engines break-in just fine on synthetic engine oil. General Motors has run hundreds and hundreds of engines on dynomometer durability cycles and not one failed to break-in. Break-in on todays engines is practicly a non-issue because of the precision machining and assembly that takes place. I have never seen a General Motors engine that had a problem because it didn't break-in properly due to synthetic oil. To suggest that synthetic oil prevents proper break-in is just passing on bad information. Every Cadillac engine built today is filled with synthetic engine oil. These engines are not built any differant because they are filled Mobil 1 at the assembly plant.

My 2005 CTS came with synthetic oil. It has never used any oil in its 30,000 mile of existence. I ran it the first year on the oem Mobil 1 (approx. 9,000 miles) but have used Amsoil every year since. About due for my my 4th oil change in Nov. I have never seen the OLM light come yet but I still change it every fall no matter the miles. Miles mean nothing me with synthetic oil in there. Have used synthetic oil for many years and consider everything else 2nd best.

I changed my 2008 GMC over to synthetic at about 1,000 miles. The engine, trans and both differentials.

I totally agree with you! When I get a new vehicle, (my newest right now is a 2005 Silverado) the first thing I do when I get it home, (usually 50-100 miles on the odometer) is grease the chassis with Mobil 1 chassis grease and drain the non-synthetic engine oil and install Mobil 1 Extended Performance engine oil. Amsoil is a very good product in my opinion and I have used it in the past and currently have some on my shelf.