I do my own oil changes and would prefer to do the DCT filter too. I have already done an oil change before it got put away for the winter late last fall. At $60 for an oil change, I can't barely get one decent dinner out for that, so it's noise level money.

 

I don't have a lift and part purchasing from my Dealership is FREE Lifetime oil Changes!

 

That is what I did at 1500 miles.

 

Based on the Service Manual of the flush procedure (Scan tool needed as you mentioned), but the description indicates the tool will cause the engine to run at 2k rpm for 8 minutes. Also there is a gear pump inside the transmission that pumps the trans fluid through the filter based on the input shaft...so wouldn't driving the car on the freeway (keeping the engine rpm over 2k) and actuating some of the solenoids (higher gears between 4th - 8th) act like flushing using the scan tool (it might not be exactly the same, but for the most part will flush the fluid through the filter and cycle some of the solenoids)??? We know the flushing procedure is electronic in nature based on the scan tool.

I have had issues with the CEL coming on for multiple DTC transmission codes, and based on the Service Manuals the dealer had, it could be debris related (car drives fine now).

So personally, I would recommend changing the filter before the 7500 mile mark as debris is generated from break-in. No harm in changing the filter early to get all the contaminants out. I think the flush procedure was added recently to the filter change procedure because of all the DTC codes popping up. If you look at the Service Manuals, there are steps done to address the codes (one of the steps involve just replacing the filter).

ALSO, please refer to the Corvette Mechanic Paul Koerner on the Corvette Blogger on WHY you should change the filter earlier ([VIDEO] The Corvette Mechanic Paul Koerner on Why GM Pays for the First Transmission Filter Change - Corvette: Sales, News & Lifestyle (corvetteblogger.com). Might convince you to change it earlier.

 

Read the previous posts and threads. FLUSH is NOT REQUIRED. Some (?MANY) are mixing those that have had Tx problems (disintegrations) generating error codes, ... Those require the flush. For those that are getting the DCT Tx filter change without any Tx problems, it is just a filter change without the flush.

 

Can you cite where that is documented from GM? So far, the only service documentation I've seen from GM requires the flush when the DCT filter is changed.

 

I believe the scan tool does more than run the engine at 2K RPM for 8 minutes.
I'll have a lot more than 8 minutes at 2K or above while shifting through gears when I bring it in for the first service.

 

It was in the other Tx thread. I'll look for it when i get a chance.

 

My early Vettes (1988 & 1993) said change oil at XXXX miles OR 12 MONTHS, WHICHVER OCCURS FIRST. It was miles as that was all you could easily access or was monitored. For my C6, two C7s and now C8 it says when OLM indicates. The OLM does not use miles! It does use engine rpm as only one of many measures. It also monitors the oil temp after a cold start and if most drives do not get the oil hot enough long enough after a cold start (to evaporate water a main product of combustion) it will reduce the 12 months. From detailed info that is available about the OLM system, it indicates other things can also shorten the time. In fact my 1993 Vette Owner's Manual (before the OLM) said if most drives are less than 4 miles change oil at 3 months or 3000 miles whichever occurs first.

Not sure why the 7500 miles is even mentioned for engine oil as other than an approximate value. The C8 Owner's Manual says this about engine oil: Check engine oil level and oil life percentage. From my experience with 2 C7's you'll get a dash warning at about 10% life left.

Don't know what the monitoring is for DCT fluid. For the DCT fluid the Owner's Manual says check the dual clutch transmission fluid life per percentage. Then note 4 says: If the vehicle mileage is near the canister filter replacement interval, replace the fluid and filter. Or change every three years, whichever comes first.

From that it would appear the fluid requires changing at 7500 miles. Sure hope they will replace the fluid when I have my filter replaced at ~4000 miles, ~11.5 months. To add 11.6 quarts of (expensive) DCT fluid in that small check fluid level hole sure needs a pump!! The comment about using a funnel in the GM DCT filter replacement instructions is fine for adding ~6 oz BUT not 11.6 quarts, the standard fill. Can't fit a very big funnel in that space. Will be interesting to see what they do.

Would sure like some clarification on the fluid replacement requirement I could bring to the dealer.

 

Thank you for posting this, more information is better than less. Actually, based on this video, I'll probably have it done. Just talked to my dealer and the car was punched on July 13th of last year so I was told as long as we have a service ticket written before that day we are good.

 

Found it - You POSTED THE ANSWER in the other thread. https://www.corvetteforum.com/forums...post1603588301

Read carefully. That procedure is for a broken Tx that needs service, not a perfectly fine Tx that is only having its filter changed for the initial time prior to 7500/1year.

A busted/broken Tx will (possibly) have crap in the fluid lines... requiring a flush, but A normal one that is getting its first filter should not and any "crap" should have been caught by the filter - hence only change the filter.

This is what I do on all of my other cars using MOBIL 1. Every 15,000 change oil and filter. In between (@7,500), I only change the filter. No need to change the Oil too every 7,500 with Mobil 1.

 

If you are referring to the Hydraulic System Flush Procedure I posted, it also states "Do NOT perform this procedure unless directed here from another procedure"
Step 1 of the DCT filter change procedure I posted above it directs you to perform the hydraulic system flush procedure.

If anything, I'd think it would be more important to perform the hydraulic system flush procedure prior to the first DCT filter change (if it is being correctly invoked) than any subsequent filter change. It would flush any residual contamination left over from manufacturing and break-in into the filter. The only contamination generated after that would be from normal wear.

 

I'm going to do the same as well, I just figure why not play the safe bet.

 

We can go in circles, but unless there is major damage to the Tx with gears,... coming apart, the filter should catch everything (should be very little) and a flush is major overkill. After all, that is what a proper filter will do unless overloaded and (if it has) bypass kicks in.

 

Logic wise, agree completely. The problem comes from if I do it myself, and don't do a flush that is now required (if it really is), and down the road there is an issue, would I get a warranty denied claim?

 

I had it done by the dealer so I am covered. That being said, I do not know if he did or didn't. I forgot to ask him today, but I will check in with him soon enough, but my guess is no. I'll try to get the actual instructions that say yes or no.

 

6/15/21 My Chevy Dealer said the flush is for repair, not for maintenance.

 

I wish I knew why the flush procedure was there. I can only envision 2 reasons (other than a mistake):
1) There is a concern that there is so much contamination in the system that it will get caught in the filter and cause an unacceptable pressure drop or cause a bypass valve (if there is one) to actuate before the next scheduled change.
2) The contamination is congealed and, over time, will break down into small enough particles to pass through the filter.

 

A dealer once told me that if I didn't like rattles I shouldn't have bought a plastic car.

My point is trust but verify.

 

You need to know the "in-service" date.