went to napa auto parts yesterday wanting to gather the stuff to change my tranny filter and rear differential fluid and the guy behind the counter couldnt tell me what transmission I had for sure or what fluid to put in the tranny or the rear end guess I should know this stuff . its a 2 wheel drive 2500 04.5 high output with an automatic and limited slip diff. is this a 48re or a 47 something?? does the rear diff take synthetic gear oil and do I need to add a limited slip addative?? what tranny fluid does my 04.5 auto call for? thanks for any info.

 

tranny ATF+4, 6 - 7 quarts , diffs 75w90 synthetic normal pulling, 75w140 synthetic for heavy pulling you have a 48RE. no additives needed

 

thanks! the bozos at napa said I had a 47 something tranny and didn t even list the 48re as an option. also said I neded to add an addative to the rear end...

 

No additive to the rear diff. I have lost all faith in my local NAPA as well, they tried to tell me Valvoline Premium blue did not exist!!!