GM Truck Club Forum banner

transmission filter and fluid change 03 silverado

27K views 28 replies 5 participants last post by  N5856Z  
#1 · (Edited)
Hello all,
I have an 03 Silverado 1500 LS extended cab with 4.8L engine

the last time the transmission filter was changed was about 64,000 miles ago.

I've heard different stories about when it should be changed .....60,000 and 100,000 miles

my truck has 235,000 miles on it now.

also are there any tricks to doing this job

Thanks
 
#2 ·
Get a trans pan with a drain plug. I believe you have 3 1/8 inch "factory deep" pan in your truck.
Dorman sells a nice one for about $37 Here's the link: https://www.amazon.com/Dorman-265-811-Transmission-Oil-Pan/dp/B002U6ELS4

Change the filter with the "proper size" trans filter for the 3 1/8 trans pan.

DO NOT EVER BUY any cork type gaskets, only get the "fiber gaskets" to eliminate future headaches.

Next, NEVER over torque any trans pan bolt. 7 to 10 foot pounds max in a crisscross pattern!!!

You will need just under 5 quarts of Dextron 6 trans fluid.

About once a year, dump the trans fluid and add another 5 quarts just like an oil change. It's much easier to do this than removing the trans pan all the time.

Here's some pictures in how to identify what you have:

Image
Image
Image
Image
Image
 
#3 ·
you have a 4wd or 2wd ?

4wd should have deep pan .. drain plug should be on it . if you have 2wd and no deep pan go to scrap yard and get one for 10 bucks ..

64K miles is OK .. I do it at 40K and change all the diff/transfer case fluids..
I also use a rubber gasket .. cork not allowed IMO... yes 7 ft LBS use a hand 1/4inch driver .. then re-torque a week later ..
rubber gaskets should last a few times on the pan removal. clean pan with mineral spirits ..

the shifter arm is the PITA .. screws hard to get... torx screws.. be careful.. the quick lube shops will bend that arm and I do not agree with that method..

deep pan takes 5 qts ..must use the proper filter deep or shallow ..shallow 3.5qts ..
 
#8 ·
Hello all, I have been waiting for my buddy to help change my transmission filter, however he has been busy and cant help for a while.
anyway he had me buy 3 gallons of ATF at Walmart. I have a 2003 Silverado 4.8L.
on the jug it states "For use in Vehicles Previously Serviceable by DEXRON -III or MERCON Transmission Fluid"
is this the correct stuff and should I get something else.
 
#9 ·
Dexron III is a banned fluid. GM banned this in 2006 for ALL GM vehicles. some auto stores DO NOT even sell it anymore...

why did GM ban this dexron III well this fluid turns to acid at 20K miles because the fluid turns to acid when it hits 200F.
the tranny shell then breaks down because of the acid III ..then debris kills it. one of the reasons GM went bankrupt.
my vehicles I switched to mobil synthetic tranny fluid in 1999 ... spec is merc dex GM .. well now the fluid to use is dexron VI.. this is the approved GM fluid for your transmission.

IN 1999 dexron VI did not exist so that is why I used the mobil synthetic tranny fluid.. aircraft engineer told me do not use dexron III and my 96 and 2000 GM 4l60 still running strong .. no leaks or shift problems.. also when I do the pan drop little debris on the magnet.

bring it back to wally mart ...I know it is very cheap LOL!!!!!!!!!!!!!!!
 
#12 ·
I changed Dexron 3 to Dexron 6 in my Tahoe 2 years ago. Now I’m going to do it in my Maxima. The difference between liquids is really huge. When it is about 77 F and you are stuck in a traffic jam the transmission starts giving good kicks to the car with Dexron 3. With Dexron 6 it’s OK.
 
#15 ·
Yea.

That is why I'm against "certain" synthetics fluids being within transmissions and pozi traction - limited slip differentials. You need a certain amount of allowed grip and slippage to have the friction plates work properly. Fluid designations are very critical to friction plate operation and yet very few people will ever follow them.

Dextron 6 was brought out because of earlier trans failure history, the lack of people not changing their trans fluid when they should. People overloading their drive train capacities by thousands of pounds.
 
#21 ·
ok today is work on truck day. I tried for a while but the drain plug would not budge, so had to drain by removing the pan.
after I got the pan removed and cleaned up, I put a torch to the plug and got it to come off.
now I'm off to auto zone to get a new drain plug......to be continued!
 
#22 ·
well I just got some bad news, apparently no one stocks this drain plug for my truck and will need to order it.
not even the dealer.
looks like I'm doing without my truck for a few days.
looks like the only drain plug available is AC Delco P/N 24233099
not sure if the drain plug for a 4L80E will work on a 4L60E trans.
 
#24 ·
The dude at the dealer called me back and said he found a drain plug for me, so I got the new plug installed and and added Dexron 6 and now the truck is good to go. it shifts a lot smoother now. So now the question is when should I drain and change the fluid again. I believe someone mentioned about once a year? I only drive this truck about 10,000 miles a year.

Thanks for the help and the tips
 
#25 ·
I only run Amsoil synthetic fluid and I change my fluid every 30k miles or every year.
 
#28 · (Edited)
ok thanks for the info, will do it this time again next year
you must check the fluid color and level when the truck is on level surface and the engine is at normal temp... when the fluid looks darker then change the fluid. if you did not do fluid changes every 40K miles or less then the new fluid will breakdown debris in the transmission.. many had problems because they did not change the fluid until 100K miles.. messes up torque converter ..GM states changing the fluid at 100K miles well that is a scam.. trucks do work and the fluid gets damaged due to the high temps..

make sure the fluid level is below the full mark.. slightly if it is above the full mark then use the drain plug to lower it..
you could have gone to auto scrap yard and get a deep pan with plug on it .. ON the Impala SS forums they changed out the shallow pan with the deep pan was $15.........scrap yard ..

I have used this product sometimes and it does a good job with shift up shifting quicker , smoother.. old vehicles need to use this https://www.amazon.com/Niteo-M1410T...code=qs&qid=1563887886&s=gateway&sourceid=Mozilla-search&sr=8-1#customerReviews