Transmission fluid question

I have a 98 GMC K2500 with a 5.7 and it is used mostly to pull my 24 travel trailer around.

I was wondering what brand and type of tranny fluid is the best for towing conditions?

I was also looking at a B&M transmission pan that has a 3 quart extra capacity versues the stock pan and it is aluminum. It is kinda pricey at almost $200...Do these things really work ??

I have a 98 GMC K2500 with a 5.7 and it is used mostly to pull my 24 travel trailer around.

I was wondering what brand and type of tranny fluid is the best for towing conditions?

I was also looking at a B&M transmission pan that has a 3 quart extra capacity versues the stock pan and it is aluminum. It is kinda pricey at almost $200...Do these things really work ??


the use of dexron VI is a replacement of the defective dexron III , is a start.. then installing a larger deep pan with the proper filter will reduce the heat. adding the tranny cooler in front of the condenser unit is also needed.. towing on grades in warm temps all this will keep the fluid from getting too hot..

dexron VI is a synthetic fluid now recommended by gm for our transmissions...dexron III failed to protect the transmission from failures due to it turning into acid..

So if I want to change the trans fluid to the dexron 6 can I just drop the pan or does the fluid in the converter need to be flushed out too??

So if I want to change the trans fluid to the dexron 6 can I just drop the pan or does the fluid in the converter need to be flushed out too??


it would be best since this is an old vehicle to replace the fluid slowly.. with the new pan and a drain plug after the first fluid/filter change drain out the fluid after a few hundred miles and refill with the dexron VI...

flushing out the converter will cause debris to start to loosen up and cause issues...with a gradual shift to the synthetic the pressures will increase ,,,,,, after 3 fluid changes the transmission will shift faster/less delay because this fluid compresses better at higher temps than dexron III...

OK, 97 K1500 So how do you know if you have dexron 3 or 6 or?
Tranny was replaced at the dealer for the previous owner about 8 years ago.
Thanks,
Bob B

OK, 97 K1500 So how do you know if you have dexron 3 or 6 or?
Tranny was replaced at the dealer for the previous owner about 8 years ago.
Thanks,
Bob B

in 2006 GM deleted the defective dexron III..dexron VI is now to be used ...dexron III cost GM too much in warrantee damages due to its turning into acid at a very early time in use...could not take the heat generated..

I lucked out as I was told of this in 1998 by a aviation engineer ..I used and still use mobil synthetic transmission fluid, lucky me no tranny issues..I still replace the fluid every 30-40,000 mi and I am good with all my vehicles operation...