My mom has an 1989 R1500 Suburban that was her first vehicle and has driven many a mile in it, the odometer recently hit 250,000 (rolled twice) and the transmission has about had it. It has the 350 in it and a 4 speed auto. However, I‘m not sure if its the factory transmission. I can‘t read the data plate at all. I‘m going to replace it for her and I want to know where the best place to get a rebuilt trans for it that is the factory box.
Just go to a auto wreckers or junk yards for cars all you need to know is what type of engine you have and if it's long or short base it makes a differences and buy one there they give you a 30 day warranty on it it's cheaper then buying used cause they cost about the same as a new one they run $1500 to $200 thousand junk yard most $400 500 it's all where you live. that's what i did when i replace my trans on my 69 camaro. payed 300 for trans and no problem so far it's been 2yrs snice i bought it Good luck
go to your local auto wreckers and ask someone there for a used one. Or I would look for a parts truck. It will be much cheaper.