7th Mar 2010, 22:03

I have a 2003 Trailblazer 4.2 L inline 6 cyl engine with 117,000 miles on the clock.

I got the jet engine noise, slow shifting, and had a "check engine" light on for low coolant level, engine temp sensor out, or bad thermostat (not closing up tight enough).

Well, the coolant level was to the top of the cap. So either the temp sensor or the thermostat was bad. It would cost $40 to put the vehicle on a computer to tell which one of the two was bad, and the parts cost $25 each... so I replaced both parts.

I bought a temp sensor and a new thermostat (comes installed on a housing that hooks to the lower radiator hose on the alternator side of the engine). I had my mechanic, Jose, install both the new thermostat and temp sensor. It took 45 minutes for the total job, (you have to unhook (but not remove) the alternator to replace either part, so the labor time to do both is about the same as to do just one. I gave Jose $20 and a fifth of Crown Royal for the job. (Note: both the lower and upper radiator hoses are connected to engine housings that look alike. You will be tempted to want to install the thermostat on the upper radiator hose side of the engine, which requires removing the power steering pump... but don't be fooled! (Jose did this first and we both laughed!))

The jet engine noise was still there, but the engine light was out. I bought a fan clutch at Autozone ($200 lifetime warranty) and Jose came over and installed it. It took him 1 hr and 10 minutes for the total job... to remove and replace the fan clutch. Nothing but the clutch had to be removed or even loosened up to do the entire job. Some people have eluded to removing the grill, all kinds of engine components, etc. this site. I don't know why?

I also had Jose install a new transmission filter while he was at it. This job took him 1 hr 15 minutes using only a 1 ton jack in my driveway, nothing else. I gave Jose $60 cash, a fifth of Jack Daniels, and another fifth of Crown for installing the ran clutch and transmission filter. Also, I threw in a few cervesas while he worked. Jet engine noise is gone now.

17th Mar 2010, 21:55

AC PROBLEM - 2002 TrailBlazer.

We have 160,000 miles on our TB. Our current issue lies with our AC. Our problem started when my husband jump started the dead battery two days ago. Since the jump, the AC has stopped working. We had a mechanic look at the AC, he believed it may be an electrical problem as the compressor appears to be working fine. The AC blows warm air out of the defrost vents only and none the controller keys are functioning (i.e. the AC push button, re-circulating and defrost buttons, and settings knob).

Does anyone have any ideas??? Not sure if the problem is directly related to the jump or just coincidental.

We too have the same jet sound with our 2002 Trailblazer. I agree with all the others, GM should be paying for this repair. This problem should result in a recall!! I can't believe how many TrailBlazer owners have the same issue.

20th Apr 2010, 19:50

Another one to add to the list! My 2002 GMC Envoy started making the jet noise and yep, guess what? It was the fan clutch. I am furious at GMC!

19th Jun 2010, 14:42

Same exact problem. It's making the weird jet sound. I bought an extended warranty with my TB, and it's been in the shop twice for the same jet engine problem sound. They say it's the idler pulley. It just started again today... back to the shop! And does anyone know what to do? My A/C works, but it just stopped working on 4. What to replace this time??

20th Jun 2010, 13:05

The fan clutch replacement is relatively easy, and the part costs under $180 (you can find it even cheaper if you shop around). Our GMC Envoy only has 90,000 miles on it, so we have yet to have ANY problems, not even a brake job.

20th Jun 2010, 21:35

You must tow nothing with it and coast down to stopping a lot. We've gone through two sets in less than 90K miles on our Trailblazer. Never have I had a GM that made it to 100K miles without lots of work!

21st Jun 2010, 17:23

My wife and I are both car enthusiasts and former stunt drivers. And NO, we have never towed anything. We have both learned to drive with the accelerator rather than the brakes. Coasting down to stops is a GREAT way to save brake pads, why on Earth doesn't EVERYONE?? If you know you are coming to a stop, why rush up to a few feet away and pounce on the brakes?? The more gently you apply brakes, the less wear on the pads.

Riding the brakes is a classic American style of driving. You will NEVER see our brake lights come on unless we are actually STOPPING. Although we both enjoy going fast and occasionally (where we can get away with it) drive over 110mph, we drive in a smooth, gentle fashion that saves wear on ALL our cars parts. As a result we will most likely get 110,000-130,000 miles out of the original pads on our Envoy.

Our Ford just turned 35,000 miles, and while rotating the tires I checked the brake pads for wear. There was ZERO. The WORST I ever did with brakes (not counting our Honda, which was poorly built) was only 70,000 miles for the front pads on our Pontiac Grand Am. The rear pads on the Grand Am were STILL original when I sold it at 85,000 miles.

21st Jun 2010, 18:12

I find GMC vehicles to be better assembled from the factory, and more reliable than their Chevrolet counterparts.

22nd Jun 2010, 11:04

Well, thanks for proving my point. I know there is NO WAY to get 100K miles out of a GM unless you baby the heck out of it. Driving even normally like I do costs $1,000's over the first 100K miles in my experience. People talk about the transmission of the month club for Honda but Chevy trucks have the worst track record for tranny problems. I've had people ask me how many transmissions Ive gone through on mine. Guess that is the one thing I am lucky with. I do tow only in 3rd gear though. One guy I met said he was on his third tranny only pulling snowmobiles around.

Imports? Never have I had anything major fail on an import before 100K miles. I drive them all the same, so in my experience imports are better overall. Not that I haven't had decent luck with a domestic car here and there. I am talking overall based on all of my vehicles.

As far as coasting to a stop. I used to be able to stop my car with no brakes shifting all the way down into first gear, and then once I let the clutch out in first, never push it again all the way to 5th. I could even downshift without the clutch. Talk about no wear! These days though, there is a lot more traffic, and I have people pulling out in front of me everywhere I go, and everyone goes so fast around here you have to mesh in or get run off the road. I never slam the brakes on, and always leave plenty of space between myself and the car in front of me. I also almost never give it a lot of gas off the line. I don't baby my cars to a ridiculous point as they should last if they are decent.