Difficulty

Moderate

Steps

11

Time Required

                          2 hours

Sections

1

  • Oil Change and Oil Filter
  • 11 steps

Flags

2

In Progress

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  • Back2002-2009 Chevrolet Trailblazer

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Introduction

The LL8 (Vortec 4200) is one of the most reliable engines that GM has produced. It was listed on Ward’s Best Engines list from 2002 to 2005. With proper care, it can lost for well over 200k miles.

The author recommends to always use a full synthetic motor oil, and to change every 5k-10k miles. However, there are many varying opinions on oil changes online, and a simple google search will prove overwhelming. Just remember: it is always better to change your oil too soon, rather than too late.

Useful sources: “GMTNation,” “Trailvoy” forums for general advice and questions. “Bob is the Oil Guy” forums for oil information. “Truedelta” for aggregrated vehicle ratings and common issues. And, as always, iFixit for all your right-to-repair content!

Note: Do NOT rely on these instructions for any of the V8 engines, or any other model year of Chevy Trailblazer. A different engine will take different amounts of oil and may vary in design. A model year outside of the 02-09 range will take different amounts of oil and vary in design. Use caution.

What you need

Step 1

              Warm the Vehicle
  • Begin first by driving your vehicle around until it reaches normal operating temperature. Usually 15 minutes of driving is sufficient.
  • This allows the oil and any particulates to fully mix, and allows the oil to flow better when draining

Begin first by driving your vehicle around until it reaches normal operating temperature. Usually 15 minutes of driving is sufficient.

This allows the oil and any particulates to fully mix, and allows the oil to flow better when draining

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Step 2

              Cool the Vehicle
  • Park your vehicle and allow it to cool off. The goal is for the oil to be warm, but not hot.
  • Do not immediately attempt to change the oil. Doing so will burn your hands. Allow, at minimum, 30 minutes for the engine to cool off.

Park your vehicle and allow it to cool off. The goal is for the oil to be warm, but not hot.

Do not immediately attempt to change the oil. Doing so will burn your hands. Allow, at minimum, 30 minutes for the engine to cool off.

Step 3

              Jacking up the Vehicle
  • Place the hydraulic floor jack underneath the front of the vehicle. Jack the vehicle up from the front frame crossmember. Place jack stands underneath the frame, to the rear of the front wheels. Lower the vehicle such that it is resting on the jack stands.
  • Always jack your vehicle on a smooth, even surface, away from traffic.
  • Always use jack stands. Do not rely only on the hydraulic floor jack. Hydraulic floor jacks can fail under load.
  • Always jack from the vehicles from the frame, not from any other area, body panel, or part. Failing to jack from the frame may cause the vehicle to fall.
  • Consult a trusted professional if you have any doubt on jacking up a vehicle. Being crushed by a vehicle can kill you.

Place the hydraulic floor jack underneath the front of the vehicle. Jack the vehicle up from the front frame crossmember. Place jack stands underneath the frame, to the rear of the front wheels. Lower the vehicle such that it is resting on the jack stands.

Always jack your vehicle on a smooth, even surface, away from traffic.

Always use jack stands. Do not rely only on the hydraulic floor jack. Hydraulic floor jacks can fail under load.

Always jack from the vehicles from the frame, not from any other area, body panel, or part. Failing to jack from the frame may cause the vehicle to fall.

Consult a trusted professional if you have any doubt on jacking up a vehicle. Being crushed by a vehicle can kill you.

Step 4

              Preparing to remove oil
  • Pop the hood of the vehicle. Remove the oil cap. Crawl under the vehicle. Remove the panel covering the drain plug. Place the oil drain plan directly underneath the drain plug.
  • If you are worried about getting oil on the ground, place a large tarp underneath your oil drain pan

Pop the hood of the vehicle. Remove the oil cap. Crawl under the vehicle. Remove the panel covering the drain plug. Place the oil drain plan directly underneath the drain plug.

If you are worried about getting oil on the ground, place a large tarp underneath your oil drain pan

Step 5

              Draining the Oil
  • Using a 15mm socket, remove the drain plug and allow all oil to flow into your oil drain pan.
  • This may take some time. Allow all oil to drain until it is just dripping
  • Motor oil is a hazardous material. Do not splash into your eyes or mouth. If this happens, attempt to wash the eye or mouth out, and immediately consult a physician.

Using a 15mm socket, remove the drain plug and allow all oil to flow into your oil drain pan.

This may take some time. Allow all oil to drain until it is just dripping

Motor oil is a hazardous material. Do not splash into your eyes or mouth. If this happens, attempt to wash the eye or mouth out, and immediately consult a physician.

Step 6

              Oil Filter Removal
  • Place your oil filter wrench on the oil filter. Twist to remove, making sure not to spill any oil, as the oil filter will be full.
  • The oil filter is located towards the front of the vehicle, towards the passenger side.

Place your oil filter wrench on the oil filter. Twist to remove, making sure not to spill any oil, as the oil filter will be full.

The oil filter is located towards the front of the vehicle, towards the passenger side.

Step 7

              New Oil Filter
  • Coat your new oil filter’s gasket with some new oil. Hand-thread it on, and torque as the oil filter instructions indicate.
  • Do not cross thread the oil filter.

Coat your new oil filter’s gasket with some new oil. Hand-thread it on, and torque as the oil filter instructions indicate.

Do not cross thread the oil filter.

Step 8

              Replacing the drain plug and cover
  • Clean the threads of the drain plug. Re-insert the drain plug and tighten to 19 ft-lbs. Reassemble the oil pan cover.

Clean the threads of the drain plug. Re-insert the drain plug and tighten to 19 ft-lbs. Reassemble the oil pan cover.

Step 9

              Lower to Ground
  • Raise the vehicle again with the hydraulic jack, remove the jack stands and wheel chocks, and slowly lower to the ground.

Raise the vehicle again with the hydraulic jack, remove the jack stands and wheel chocks, and slowly lower to the ground.

Step 10

              Adding Oil
  • Place a funnel into the oil-inlet hole at the top of the engine. Fill with 7 quarts of 5w-10 oil. Replace the oil cap.
  • Some older engines have oil seepage issues. There is evidence online that using a 10w-30 oil is more effective than a stop-leak product, but use your own discretion.
  • GM recommends using an oil that meets GM Standard GM6094M.

Place a funnel into the oil-inlet hole at the top of the engine. Fill with 7 quarts of 5w-10 oil. Replace the oil cap.

Some older engines have oil seepage issues. There is evidence online that using a 10w-30 oil is more effective than a stop-leak product, but use your own discretion.

GM recommends using an oil that meets GM Standard GM6094M.

Step 11

              Start the Engine
  • Start the engine. Ensure that there is no oil leaking and that there are no abnormal noises (metal scraping, knocking, etc). Reset the oil change light in the dashboard. Take the vehicle for a drive.
  • Don’t always rely on the oil change indicator, as it may fail. Be sure to write down and keep track of your vehicle mileage to determine oil change frequency.

Start the engine. Ensure that there is no oil leaking and that there are no abnormal noises (metal scraping, knocking, etc). Reset the oil change light in the dashboard. Take the vehicle for a drive.

Don’t always rely on the oil change indicator, as it may fail. Be sure to write down and keep track of your vehicle mileage to determine oil change frequency.

You’re all done! Replace your oil every 3-5k miles for conventional oil, or every 5k-10k miles for synthetic oil. Opinions on oil change frequency vary widely, but always remember to never have your oil changed at a “quick change,” “quick lube,” or car wash business. Always do it yourself using the proper tools and proper supervision, or have a reputable mechanic perform the change.

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                    Joshua F

Member since: 10/07/2020

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Joshua F - Oct 7, 2020

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I will be updating this guide with images and further explanations that reference the photos. Without images, it is difficult for the beginner to visualize what the oil change entails.