Quote:
Originally Posted by Big Dave
Congrats on the new diesel.
I had a 83 K2500 diesel pickup for 17 years and 305,000 miles, so have some insight into this vehicle.
Buying a used 6.5 my first advice is to have the engine, radiator, and heater professionally acid-cleaned and back-flushed. these engines are touchy about being over-heated. I'd still have that old 6.2 but the engine got hot and cracked the block at the No. 8 cylinder.
I completely agree with Post #8:
" The single best FE improvement I made to my gas 1991 K2500 was swapping the 4L60 Auto Transmission out for a NV4500 Manual Transmission. I know you may not want to do that right now, but it would be something to keep in mind."
That a minimum 2 MPG improvement just waiting to happen. Further, and maybe more importantly, you'll be ditching a transmission that was never intended to be used with a diesel. Even the 6.5 makes a lot of torque at low RPM. so much so that the torque converter cannot pump enough fluid to keep the transmission cool. A cooler does not help. Fluid flow is simply inadequate. My old 6.2 had a 700 R4 and later a TH400 and I trashed them seven times. Spectacular failures - scattering parts an fluid down the road. Lots of plastic parts obviously melted and ferrous metal parts turned blue. The stick completely eliminates this problem. The conversion is old hat in the Chevy pickup/Suburban community.
There are uncorroborated stories out of GM about a 6.2 suburban with 2.73 gears that could get 30 MPG. I don't see why you couldn't get 23-25 with some modest effort.
Here is your gold mine for 6.5 information.
The Diesel Page - for the 6.2L, 6.5L, and Duramax 6600 (6.6L) GM Chevrolet and GMC diesel engines.
They've been at this for nearly two decades. |
Yeehaw, Thanks! (And while anyone else is reading who contributed, Thanks to you too.)
Where could I get the radiator, heater and engine acid-cleaned and back-flushed? Pittsburgh isn't too far of a drive for me.
I may change the transmission eventually, but for now the automatic one is staying.
Also, This vehicle is going to be towing things like a 4,700-5,400 pound car + trailer so I'm not going to change the gears in the rear. I'll be changing the differential fluid, though.
And so far, the vehicle has a roof-rack on it and I'm not sure if I can remove it or not.