3 Q's: Ever hear of a 6.5T with "1 wire pump", increasing towing, 700R4 into 1028A1 ?

[Geardoc]

3 Q's: Ever hear of a 6.5T with "1 wire pump", increasing towing, 700R4 into 1028A1 ?

I have a 1028A1 with the NP205. The 6.2 is now in Detroit Diesel heaven, it is kerplunk. Webbing of the block is cracked, the crank has two hairline cracks, and the doggone bearings on rods and mains are shot. Darn truck only only has 18k miles.

I have acquired an early 6.5 Turbo that had no miles on it, as well as what I assume is it's 4L60E 2WD as it has the tailshaft with the U-joint mount in it.

This is an early model, and according to the previous owner it is a single wire pump model and the only electronics on the engine is a 12v kill switch on the pump. I've never heard of such a thing.

After some searching I found a 700R4 K-series, it has a new clutch set and new everything except for the valve body. The trans shop was building it out the behind for an off-roader and he quit paying right as they got to the valve body. He abandoned it, I have machine tools and did the trans shop owner a solid, and he sold me the transmission for $20 after it set for two years and the kid said screw it and left the shop with a pretty hefty bill. I am going to redo the valve body.

I want the truck to get the best compromise of towing capability and gas mileage.

Speaking of which, why is the towing rating so low on 1.25 ton truck ? Is there anything I can do to incease the truck's towing capacity ? I would like to tow my John Deere 450 and hudson 12ton low boy.

What do I need to do to make this happen ?

 

[Warthog]

The first 6.5 came out in 1993. It still had the DB2single wire injector pump. A few 1994 also had it but the majority had the "new and improved" DB4 electronic IP. The 1994 blocks also have a reputation of being a weak block.

My personal opinion you will be disappointed in the performance of the truck towing such a load. The tranny will be a weak point and the overall speed will be low. Buy a duramax.

 

[Chaski]

When I want to tow my buddies 25K gooseneck with something heavy on it I go for my other pickup which has a Cummins 6BT and a New Venture Gear 5600 transmission. Asking a 700R4 to deal with a 14 ton trailer is asking the impossible. A 700R4 is a great transmission to pair up with a 6.5, if it is built properly and you stay within it's limitations. I go run to the woods and get fire wood with my 6.5/ 700r4 combo. I tow small trailers with it, but I don't ever exceed 12,000 pounds gross combined, and rarely exceed 10,000 pounds. The 700r4 is the same as a 4l60. The genius behind GM's auto transmission naming is that the "6" in 4l60 designated that it was designed to push around 6,000 pounds 24/7. If you want to haul a heavy load you need to go Cummins or Duramax with a manual box or an Allison.



About the "one wire" pump. I think the guy was referring a DB2 vs a DS4 pump. The DB2 is a mechanical pump, is simple and is reliable. It connects with 2 wires, the shutoff solenoid, and the advance solenoid. The DS4 is electronic and has a bad reputation because the PMD (little computer) was mounted on the pump where it gets cooked in the valley of the engine. If the PMD quits, so does the engine. If you have a choice I'd run a DB2 out of simplicity and reliability. You should be able to identify your pump by reading the nameplate or comparing how it looks to pictures.