Tranfer case blue fluid change

I finally realized that chevy had a new fluid for 236/246 cases. Got enough to do my blazer and suburban. Did the blazer first and now I get the service 4x4 light on occasionally. WTF?
Light comes on randomly and is gone when I start the truck again. I tested shifting while light was on and had no problems. When my TCCM was bad light was always on even after shutting it off over night.

Any ideas? Do the codes stay in the computer after light goes out?

I am now very leery to change the suburbans now.

I finally realized that chevy had a new fluid for 236/246 cases. Got enough to do my blazer and suburban. Did the blazer first and now I get the service 4x4 light on occasionally. WTF?
Light comes on randomly and is gone when I start the truck again. I tested shifting while light was on and had no problems. When my TCCM was bad light was always on even after shutting it off over night.

Any ideas? Do the codes stay in the computer after light goes out?

I am now very leery to change the suburbans now.

If light is on you need to get transfer case codes and post back code.
Yes code should be in memory codes even if light goes out.
Also clear code and see if it comes back.

Changing fluid should be done on them ever so often and should not affect the service light.
On the sub you should service it with the GM blue transfer case auto trac fluid just make sure it has the 236 /246 transfer case.
And do not confuse the auto trac fluid with the blue std transmission blue fluid.

If light is on you need to get transfer case codes and post back code.
Yes code should be in memory codes even if light goes out.
Also clear code and see if it comes back.

Changing fluid should be done on them ever so often and should not affect the service light.
On the sub you should service it with the GM blue transfer case auto trac fluid just make sure it has the 236 /246 transfer case.
And do not confuse the auto trac fluid with the blue std transmission blue fluid.

I'll get it read. Seems odd that it would start to happen right after I changed the oil.


The sub is the 246 with auto button, like the blazer is the 236 with the auto button.



Any way to read the code with out a reader? OBD2 reader won't do it.

Was the dashboard switch

Was the dashboard switch

Thanks for posting back how it went.
Did the codes point you to the switch?

That's what my mechanic said the code pointed to and I had another laying around and put it in.


The light for 4x4 wasn't always lite when you engaged 4x4 for a while before the codes started to appear.

Thanks for the info and.
Good Luck