1988 D100 - removing 318 + transmission. Will be replacing engine & have transmission rebuilt.
Looking for any good info on the process. Thanks.

 

Is this your first time or have you pulled engines/transmissions before?

Basics always make sure everything's unhooked, I'm less familiar with the 100 platform so i cant give much details specific to the chassis as just general knowledge

If its actually a D100 then you can probably pull engine and trans together if its a W100 you'll want to pull the transfer case, and maybe the trans too before removing the engine, biggest thing to remember if its not coming easy figure out why, don't just yank/hammer/pry beat it together/apart, these trucks have been on the road a long time and look pretty crusty at times, got to decipher if tis corrosion or something else holding you up

 

At 332,000 miles, I had to replace the engine in my '84 W150. (You'd think they would last longer than that!) Those sit a little higher and my picker wouldn't lift high enough to clear the radiator support. I removed the radiator support (the part your headlights, radiator and all that are mounted to) but left the fenders on and pulled it straight out.

Take lots of pictures how everything goes together before you pull it apart. I prefer to pull the units together as one piece then separate them on the floor. Block the wheels then pull the driveshaft. Put a rolling floor jack or transmission jack under the transmission to support it. Then you remove the rear cross member. Undo all the wiring and hoses, get some paper tags and label each one as to where it goes. With the radiator support removed you can lean right in there and work. Once everything is unhooked, you can now unbolt your motor mounted. If you're pulling straight out, you may not even have to remove the hood.

Once it's out, I'd clean the engine bay up. Why not, this is when it's easiest. You can also work on things that are normally hard to get to, like rubber bushings. Are you putting a rebuilt or used engine in it? If it's a used engine, I like to go through them before I drop them in. With the engine on an engine stand, it's easy to replace the timing chain set, the oil pump with a high volume, not high pressure unit to compensate for worn bearings, replace the expansion plugs with new ones and while they are out, rinse the block to get all the rust and sand from casting out. You'll be surprised how much is still in there after all these years. When you get done and all the gaskets are replaced and sealed nice, give it a coat of paint. A nice clean engine just seems to run better and cooler.

 

I'm used to taking the trans out the bottom and engine out the top/front because that's all you can do on cummins truck (unless you lift the cab off).

 

just disconnect everything and toss all the wiring/computer on the engine, remove the hood and then pull it out. can be done in a couple hours.