Tranny Question

98GMC_20 · November 11, 2006

Ok, I have a 1998 GMC ext. cab short box 4x4 and I went to get my tranny flushed out yesterday and when the mechanic went to find the right filter out of his catalogue book he noticed that none of the 1998 filters would work on my truck because apparently I have a deep pan and the filters a little larger than the shallow pan. The place he found my filter in his book was under the 1999 GMC trucks. Does anyone know why this would be?

98GMC_20 · November 13, 2006

Come on I see just about 30 people have read this and not a one has replied, someone has to have an insight on this.....

SPARK CHASER · November 13, 2006

Apparently between 1997 and the 1998 model years GM came out with the 4l60e-b transmission which has a slightly deeper pan than the 700r4/4l60e does.

98GMC_20 · November 13, 2006

Thats weird because the mechanics Fram Filter book didn't have a deep pan filter listed for my 98 and previous trucks, he had to go up to the 99' trucks listing the first year for the new half tons. They had the new style half tons then but the 3/4 tons and up hadn't changed styles yet, so I wonder if I have 3/4 ton tranny or something....I have no clue

Rookie · November 13, 2006

1998 1/2 tons produced after 11-14-97 have the deep pan any thing prior has a normal pan. why i dont know

98GMC_20 · November 13, 2006

I just checked my RPO Codes for my tranny and all it says is I have the 4L60-E and Heavy Duty Transmission Cooling System

Valsport · November 13, 2006

i dont think the deep pan has an RPO (correct me if wrong of course). typically when buying a trans filter kit I am asked for my VIN, and the dealer's system/auto parts system will match off VIN. otherwise going off model, year, motor ect ect... you get multiple filter kit part no. matches. I wouldn't worry too much about "WHY" you have it or "WHY" its only listed in the 1999 model year spec in HIS book, I'd just be glad you have a deep pan (more oil=cooler oil) and just know to get the deep filter kit in the future.