All, I have only owned my Silverado for about 5 weeks. I have driven it about 1000 miles. I purchased it about 120 miles from my town. I had it ...

All,

I have only owned my Silverado for about 5 weeks. I have driven it about 1000 miles. I purchased it about 120 miles from my town. I had it checked out, and no mechanical defects were detected. The truck has 103000 miles on it.

I have noticed when the truck is cold it seems to have some difficulty changing from third to fourth gear. When the vehicle is warmed up, it shifts fine. I tried checking the tranny fluid this evening. I didn't shift to every gear like the owners manual said. It looked like it was maybe a little low, but I didn't do a cold check yet.

I was due for a transmission fluid and filter change at 100000 miles. I don't think I would fail under the other schedule for 50000 miles. I have heard not to change it if you aren't sure of the past frequency it was changed. Is there any truth to that? I am thinking of taking it in for that service tomorrow. Could it be causing this issue if it was a little low?

This is my first GM product, so I though I would ask the experts.

I would take it to GM and cross your fingers...What we do (on the ones that aren’t under warranty anymore…the farm trucks)
Is take it in to dealership for a tranny flush. Then drive it about 1000 miles then we replace fluid and filter on our own. We do this every 25K on farm trucks… regardless.

Seems the dealerships just flush them anymore. They say that it cleans the filter too and gets everything out of the bottom of the pan but believe me it doesn’t. But they claim it’s the best because it changes the fluid in the torque converter. That’s just what we do…its a lot cheaper than a transmission. My buddy had a 99 ½ 1500 4wd and his tranny went out cost him 2,500...


Hope that helps and hope your tranny is OK.

I appreciate the advice. Unfortunately, I don't really trust our local dealership.

I have a shop that is I have been using for several years that I will be using. What is the benefit of flushing and then changing the fluid 1000 miles later? I am not too familiar with that.

When you drop the pan and change the filter, you are only changing a portion of the oil. By doing the flush THEN changing the filter not only do you know that 100% of the fluid is new, but you get a chance to change the filter after the flush moves any dirt into the old filter. End result - 100% new fluid and a new filter along with a chance to clean a pan. This would be my approach as well at your mileage.

Thanks! I have been reading up on the flush and it sounds better that a simple fluid change. Have you heard of any instances where the flush process could damage the transmission? I had a brake job done recently an the service advisor said they don't recommend servicing the transmission if it has a 100000 miles if its running okay. Does that seem right to you? You hear a lot of conflicting information.

I have heard some of the horror stories of transmissions that were never serviced until over 100k miles then flushed and "knocked things loose" causing more trouble than good. This typically seemed to be the case with older transmissions with lots of years on them. Like you said, lots of conflicting information, but as long the fluid looks decent now and the truck wasn't abused its whole life, it should be clean enough to handle a nice dose of fresh fluid. Others can feel free to weigh in, that's just my opinion.

Anyone who does not drop the pan, replace the filter before doing any flush, stay away. YOU MUST DROP THE PAN or all will do it circulate any debris that has settled to the bottom of the pan. The filter cannot be flush backwards.

The only people who recommend flushing the trans with a machine are those who own a machine and are selling you the service. Talk to a transmission pro and they will tell, don't do it.

Read this Bulletin from the Filter Manufacturers Council

Even if the fluid evacuation method is desired to remove the used transmission fluid,
the pan should be removed also, and an inspection should be made of the pan
contents, fluid, and filter to determine the condition of the transmission. Aluminum
filings in the pan or iron filings on the pan magnet are signs of internal wear and may
give light to potential problems in the transmission. Transmission service is
performed for preventative maintenance. Evaluating the overall condition of the
transmission by removing the pan should be part of this preventative maintenance
also.

Mike,

Hopefully I can learn something different here - the shop I had do the "flush" I had before simply had a supply line and dump line hooked up to my cooler lines on a previous vehicle, the transmission pump was used to circulate the fluid through just as if the vehicle were going down the road, no excess pressure to push debris around. Then the pan was dropped and new filter put in. The shop explained this was done so that the new filter wasn't instantly compromised by the old fluid that was in the system. Could be I had the wool pulled over my eyes, but that process made sense when it was explained to me. Are there systems out there that force enough pressure to knock debris loose? Not disagreeing with you in the least, looking to debunk the possible myth I have heard in the past. Thanks!