Charlie D. wrote:
The OP asked about a Chevrolet transmission not a Ford. If he reads and follows the manual it says Chevy does not recommend a flush. He will be better off following his manual than getting conflicting opinions from owners of the BIG 3. Now I have expressed my opinion.:)
I just love folks that say this or that says this or that and fail to provide any verifiable source to backup their for what I can only call unsubstantiated statements and in your specific case I think your contention that the owner's manual specifically states not to flush the transmission is incorrect and that specific recommendation is no where in the owner's manual for the specific vehicle we are talking about which is a 2010 Silverado.
I actually downloaded the 2010 Silverado Owner's Manual which was 626 pages and no where in those 626 pages does it mention anything about flushes and the transmission. You failed to provide any reference except some reference to the owner's manual so please give us the page nr. and topic title where you find your contention that the transmission should not be flushed or I would advice folks to disregard your post as your personal opinion and nothing more. BTW I have already agreed that certain types of flushes are not IMO a good way to service your transmission. The document I used came from
2010 Silverado Owners Manual and the manual has the part number of 25854757 A First Printing.
I converted this document to a PDF and then did a FULL search on the word flush and what it does say not to "FLUSH" is the engine oil, but does say to "FLUSH" the cooling system.
What is does say on page 6-23 is
Automatic Transmission Fluid
(4-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
A good time to check the automatic transmission fluid
level is when the engine oil is changed..
Change the fluid and filter at the intervals listed in
Scheduled Maintenance on page 7?3 and be sure to
use the transmission fluid listed in Recommended
Fluids and Lubricants on page 7?13.
A similar procedure is found for the 6 speed auto on page 6-26
Automatic Transmission Fluid
(6-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission
fluid level. The only reason for fluid loss is a
transmission leak or overheating the transmission.
If you suspect a small leak, then use the following
checking procedures to check the fluid level. However,
if there is a large leak, then it may be necessary to have
the vehicle towed to a dealer/retailer service department
and have it repaired before driving the vehicle further.
Notice: Use of the incorrect automatic transmission
fluid may damage the vehicle, and the damages may
not be covered by the vehicle's warranty. Always
use the automatic transmission fluid listed in
Recommended Fluids and Lubricants on page 7?13.
Change the fluid and filter at the intervals listed in the
Maintenance Schedule. See Scheduled Maintenance
on page 7?3. Be sure to use the transmission fluid
listed in Recommended Fluids and Lubricants on
page 7?13.
Please note in both these they say "FLUID CHANGE" and what I have described doing with with the tranny itself or with the proper machine is exactly that a "FLUID CHANGE". It's not as is normally referred to as a "flush" nor is it a "drop the pan" and fill so what I have described is if you want to follow the owner's manual the closest you can get to a "fluid change". As I have already provided documentation that simply dropping the pan and refilling only changes 5 of the about 12qts in one Chevy tranny and I don't call that by any stretch of the imagination a "FLUID CHANGE". If you do O.K. have at it, but realize what you are actually getting and accomplishing which like one member that thought that got 75% of the fluid changed was way off in his numbers and is basically like the example I gave is doing an engine oil change and putting most of the old oil back in and only adding very little (i.e. less than 50%) new oil.
I leave it to the Chevy owners to figure out the best way to do an effective "FLUID CHANGE".
45Ricochet and 352 your posts are IMO not helpful and do nothing to help or add to the topic being discussed here and I am at a loss to understand why folks like you post the useless type info that you do. I think you should be here to help folks and leave whatever personal agendas and what I can only call "childish" comments such as "Personally I only flush when going #2" you might have at home where they belong.
Finally the apple and oranges statement is questionable here since regardless of make transmissions in their cooling systems are very similar and all have a line out which goes thru the coolers and then a return line in and what I have described for my 4R100 is disconnecting the return line and letting the pump in the transmission push all the fluid thru the internal passages in the tranny and the TC and collect that fluid from the return line, replacing the lost fluid via filling the pan before it runs the tranny dry. This procedure or something very similar should be applicable to many other makes and models of transmissions, but one needs to consult the people actually knowledgeable to get the specifics which at this point no one that has posted in this thread including me has shown that specific level of expertise.
About the only thing I can add in closing is Q.E.D.
Larry