Rabbitmurray

I have a 04 Blazer that makes sort of a grinding noise when you let off the gas pedal and let the car coast. the RPM's fall to idle and it sounds like it is between gears, sometimes it makes this sound shifting from park to reverse, I changed the Fluid, Filter and the Transfer case motor but the sound is still there. please help!

MT-2500

What transfer case?
Does it do it in all ranges 4W 2W 4Wlow?
Does it do it with transmission in reverse or low or second or drive or OD or all gears??

Is front axle locking in good?

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Remember proper testing gives us the answer to many problems.
MT

Rabbitmurray

the 4wd still works fine in all ranges, the noise comes in 2 hi only while driving when you take you foot off the gas, does not matter what speed.

MT-2500

Not good.
What transfer case?
Check the electromnics on transfer case.
Check transnmission for cracks or broken cases.
Check drive line and u joints.
If nothing shows up better find a good repair shop and have then check it out.
Good luck and let us know how it goes.

__________________
Remember proper testing gives us the answer to many problems.
MT

Rabbitmurray

I have check'd under it, all is clean and dry, I have never had it in the mud/off road at all, I took it to my local Trans shop, he told me the trans case motor was bad, so i changed it, everything seems to be in place under there, The only thing i know to do now is go trade it in. i hate to do that it has been a wonderful car with no problems until now, It is hard to find someone you trust to pull the case off and open it up. Thanks for your quick replys! I will let you know what happens!

MT-2500

Main thing is to make sure it is transfer case problem.
May take proper testing by a transfer case trained tech.
Was it checked for codes or any codes pulled?

A 04 should be worth a transfer case replcement
If it is the transfer case they have rebuilt transfer cases.
Gm parts department has them and other places to.
Good Luck

__________________
Remember proper testing gives us the answer to many problems.
MT

Rabbitmurray

It was checked by a local Trans shop, I will check on how much thet are! There were no codes when he checked it.

MT-2500

Might pay to get the dealer or another good repair shop recheck it.
Good luck

__________________
Remember proper testing gives us the answer to many problems.
MT

blazes9395

Are you sure its the transfer case? This sounds like the front differential is paritially engaged. When you let your foot off the pedal while coasting, thats when vacuum returns from the engine again, and is a common indication of a partial engagement. My advice would be to check the front differential. Get the front up and make sure your CV joints(inner and outer) are good, specifically the driver's side. Make sure its not broken or worn out. If that checks out, check the vacuum switch either under the hood on the firewall (if its a 4 button 4x4) or on the transfer case itself(if its a 3 button 4x4 switch).

Best way to do this would be to check for vacuum at the actuator under the battery. If the truck is in 2wd, then there should be no vacuum at the actuator. If there is, repalce the vacuum switch. If its in 2wd or 4wd and the vacuum is intermittant or weak, also again, check all connections but most likly a vacuum switch again.

Rabbitmurray

ok thanks for the info! I will check the things you said and I will let you know what I find! Thanks again for responding!