Olds 455 mate up to a '79 350 Diesel trans?

[3QTRTONS]

Buying 2 GMC Diesel SWBs from another Member ()......
Wondering if I can pull the 350 Diesel out of this '79 and install a '76 Olds 455, using the 'Diesel' trans?
ANYONE done this...... appreciate the input!

Btw, BOTH are going "back in service"

[BLE 'BURBAN]

You sure can. The 350 diesel was an oldsmobile 350 block. so if it's still got the 350 diesel in it then you've got half the battle taken care of.
Note that the engine mounts on the olds engine are bolted to the front and center boss's on the engine to get them to line up with the frame mounts. I found out the hard way I had mine too far back on the block when I dropped my olds455 into my old '74 C10. (pulled it outta my cutlass tranny and all thinking it would "just bolt right in" )

[3QTRTONS]

Awesome! I haven't ID'd the rear end in the '79..... hopin that its gonna be liking the new engine. If not, I DO have a GMC '75 rear thats either 3.73 OR 4.11 (could be interesting).
So keeping the Diesel TC & governor is ok? Low end is what I wanna end up with...... can't get away with speeding too much around here. Rather spend the $$$ I got on more TRUCK PARTS anyway.

[Corts60]

I could be wrong but I think you will need to change out the torque convertor. . .

Also, if you are not keeping them diesel and aren't interested in any of the diesel emblems, I would be interested in them.

Let's see some pics!

[KQQL IT]

I got a diesel 12 bolt at a junkyard. Was 2:73 was great with a 27" tire
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[86c20]

you will have to change the tc as the stall will be low the rear end my be a hight gear then you think as some where 3.73 as the 5.7 are gutless. all so the 350 diesel is a good motor but got a bad rap for the injection pumps being junk. some poeple will buy them right up and all the parts to.

[Corts60]

Originally Posted by KQQL IT

I got a diesel 12 bolt at a junkyard. Was 2:73 was great with a 27" tire
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The early diesels usually were paired with these tall gears which made amazing mpg numbers and rendered them completely useless to tow anything or move out of their own way. I run 3:73's in my diesel and it is an excellent combo.

[BLE 'BURBAN]

My '74 C10 had a 12 bolt with 3:07 gears in it. Got great highway mileage and with the massive torque from the olds 455, I was more than capable of chasing down the occasional 'vette or camaro or 'stang all the while they're wondering what the he** I'm running.....A ROCKET ENGINE!!!!! LOL

[3QTRTONS]

So I'm looking to get another TC. Dunno s--t from green apples bout that (ANY 350 TC?), but I'm sure gonna see what the rear gear is first....
This is my first SWB & I wanna do it the right way....kinda like Jr Prom nite.

I'll get pics in the flow... haven't paid the final $$$ yet... These 2 weren't on my radar.

Hey Corts 60, you are 1st in line when the '79 Emblems go up 4 sale. The '85 that my son talked me out of is a Sierra Grande on the SPID, but has High Sierra Diesel fender emblems! Never seen em before; and he ain't givin em up! He's all excited - SWB that'll have "the look" AND can get 25mpg!

The 350 Diesel stuff is going to be up 4 sale as soon as I pull the motor. The people that have those would love to get hold of some original parts for backup I'm sure.

I really appreciate the feedback, keep it coming! Pix soon......

[Corts60]

Hey bud, I think you'll be happy to know that you have two T400's coming your way, not T350's. The T400 was the only tranny offered with the 5.7 during those years. And the axle (if original) will be one of three: 2.76, 3.08, or 3.40

[3QTRTONS]

Hey,
I'm REAL happy to hear that! IMO, any of those rears would be great with my 455! And with a T400, I could haul about anything, INCLUDING a--!!!

The '85 my son talked me out of is a 6.2 that starts & runs REAL GOOD! I'm wondering if I could use the running gear out of an '85 CUCV 4x4 Blazer for his?
3.08 front and rear, 700R4, can't remember what transfer case. Rest of the vehicle was a 2-to-make-1 deal, and I got the suspension/driveline. Oh, maybe should start this one in another thread..... not too savvy on protocol, yet.....

Pix as I get em.