Upgrade engine

[WarWagon]

Thanks ! New to diesels.jist looking to do the things I need to for better mpg.having block and heads done next week.so just looking to improve what I can.will be daily driver..I'm looking for dependable and best mpg I can get.tjanks again

Trade it on a modern 2011+ 1/2 ton Gasoline pickup. They get 4 MPG better than these IDI Diesels on cheaper fuel. Less oil and longer oil change distance as well. 14 MPG on a 6.5TD and 18 MPG on said modern 1/2 ton gas engine. As no one wants an older gas engine 1/2 ton there should be some deals out there.

Dependable is a vague term for a 29 year old vehicle. It's age causes problems while avoiding modern vehicle computer problem hell.

You have the engine out why?

MPG can be helped if you do a lot of under 45MPH driving and it's an automatic: put a better triple disc torque converter in and then lock it up at 35 MPH. Alignment and non worn out front end parts also help MPG. Return on your investment for a $1100torque converter, $550 rear end re-gear, $2000 front end rebuild ... yeah maybe not worth chasing too hard.

Speed is a major MPG factor. Time is money.

The 1993 has just a spring can for the turbo wastegate. So even with zero throttle it's generating boost in upper RPM's wasting fuel. So the question becomes what RPM and MPH are you running?

 

[daiglesteve1965]

Trade it on a modern 2011+ 1/2 ton Gasoline pickup. They get 4 MPG better than these IDI Diesels on cheaper fuel. Less oil and longer oil change distance as well. 14 MPG on a 6.5TD and 18 MPG on said modern 1/2 ton gas engine. As no one wants an older gas engine 1/2 ton there should be some deals out there.

Dependable is a vague term for a 29 year old vehicle. It's age causes problems while avoiding modern vehicle computer problem hell.

You have the engine out why?

MPG can be helped if you do a lot of under 45MPH driving and it's an automatic: put a better triple disc torque converter in and then lock it up at 35 MPH. Alignment and non worn out front end parts also help MPG. Return on your investment for a $1100torque converter, $550 rear end re-gear, $2000 front end rebuild ... yeah maybe not worth chasing too hard.

Speed is a major MPG factor. Time is money.

The 1993 has just a spring can for the turbo wastegate. So even with zero throttle it's generating boost in upper RPM's wasting fuel. So the question becomes what RPM and MPH are you running?

Frontend has totally been rebuilt. complete new ac system.new tires.something came loose in engine.got the truck for 2000 friend of mine.we have 4 6.5 engine.1 599 2 141 and 1 929.going to have 599 block and heads redone.its a very clean truck.he was getting 20 mpg before engine messed up.

 

[WarWagon]

Likely lower freeway speeds than I run. Wonder what you would get on a modern gas engine for MPG? Other than that IMO there isn't much more you can ask than 20 MPG out of it on today's fuel. Esp. if you have Winter blend to deal with.

Replace the engine oil cooler. It's a source of debris from the engine failure that will damage a rebuilt engine. Not worth any risk as they can't be flushed clean. Debris also hit the turbo bearings.

The Oil Cooler hoses: there are better out there than the quick to assemble on the assembly line GM design that likes to blow out at the block connectors. The hoses also leak at the crimps from being hotter over time than their design temp and hardening up.

Complete kits have an oil cooler and better hoses I recall like AN connections to the block.

Get a relay kit for the OPS.

If the timing gear set is available (looks like it) get one over the stretched out in 30K mile chain. The shock loads from the IP stretch the chain so bad GM had to allow 0.8" of slop in the chain. The DB2 you have calls for timing adjustment every 6 months due to chain stretch.

https://leroydiesel.com/products/timekeeper-ds4-timing-gear-set/

Get gapless rings ... HD use on OEM rings is change the oil every 2500 miles. 500 miles more to 3000 miles the oil samples in HD use get UGLY: High Soot, out of grade thicker... The blowby is the #1 indicator of bad engine health. You eliminate blowby, still, at 30,000 miles with gapless rings and can run the nearly soot free oil 4000 miles or more. You can see the marking on the dipstick through the oil at 3000 miles vs. OEM rings soot black oil.

Coated cam bearings or at least new cam bearings. This is where these engines loose oil pressure.

 

[JMJNet]

You may not get 20 mpg again after the new engine is in there.
The biggest improvement I read before was changing the Differential gear ratio.
That got nothing to do with the engine itself.

 

[blumpkin]

Thanks ! New to diesels.jist looking to do the things I need to for better mpg.having block and heads done next week.so just looking to improve what I can.will be daily driver..I'm looking for dependable and best mpg I can get.tjanks again

might be a bit late for you now,. but if you can get a set of 6.2 heads with the smaller precup, they get better fuel mileage, another thing i did that made a big difference was lowering the rear end ratio i found a set of 3:21's for my full floater rear end, and as a daily driver its great, my suburban has towed a few times with up to 6000lbs or so behind and i didn't notice any lack of power with the longer gears,.keeping the rpm back has also cut back on the drive pressure for the turbo when cruising and its all working fine,.

 

[Husker6.5]

Those super tall gears for the 10.5" 14-bolt rear are scarce as hen's teeth to find. Nobody aftermarket makes them, you just have to get very, very lucky and find a parts yard rear end that has them. Never made for the front differential in 4WD. The tallest you can go there is the 3.42 set.