Diesel Engine Bay Help

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mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
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I’m being lazy determining what the glow plug assembly is, guessing it’s the assembly on the firewall to the right of the AC assembly? Also, the power brake booster/master cylinder looks unusual too, will some of you mechanical gurus explain, please? Appears the power steering feeds vacuum to the brakes? This use to be a diesel but now 350sbc. Should I keep this setup or put in the usual setup with booster & master cylinder using engine vacuum? Thank you for your help and advice.
 

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bucket

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The hydroboost brakes are a good setup. It works off of fluid pressure rather than vacuum. It was used in 1-ton trucks with gas engines too.

The canister on the firewall is the diesel fuel filter.
 

Craig 85

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I saw one of your other posts and I'm guessing your truck is a mix of several trucks. The "M" in your VIN would indicate a 350 engine, not a 6.2L (C or J). The hydro-boost brakes are better than the vacuum style. They came on diesels and heavier trucks like my K30.

The other thing is I don't think diesels came with a full rear end. I know small block 3/4 ton 4WD had a semi float rear end. Usually after 1981 the only 4 wheel drives that got a full floater rear was a 1 ton.
 

mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
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Thank you for the responses. I’m pretty certain I will find several more surprises and I agree it’s probably several different trucks, definitely the drivetrain. I’m fairly certain though it was originally a diesel with an automatic transmission. It has the 2/4H/4L selector on the floor hump but it also has lockouts on the front differential. Is that factory? What is a semi float rear end? Good/bad and how do I identify?

I haven’t tried to use the selector or lockouts since I haven’t driven it other than around the block or move trailers around my house.

I’m trying to learn more about the truck in preparation to drive it more frequently. I’m probably going to change drive train fluids in the near future. The original paint is tangerine orange which I see underneath four other colors, I see the original orange inside the cab, firewall, fenders and the bed so it appears that’s still original.
 

mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
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Took several pics of the drivetrain so I can try to understand how 4 wheel works and maybe possible gear ratios? Hubs need to be in lock to spin when in 4H/L, correct? What model transfer case? What type differentials? I greatly appreciate your expertise, thank you!
 

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bucket

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Yeah, lock the hubs to use 4 hi and 4 low.

10 bolt front axle, np208 transfer case, '85-'86 style crossmember, 14 bolt full float axle. The rear axle has modified shock mounts, so it's probably not original to the frame.
 

mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
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Thank you, how do I go about identifying which manual transmission it’s running? I read some manual transmissions have over drive.
 

mxer147

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I compared these pics to the manual transmission ID thread but I couldn’t really make a clear identification. My lower back has been bothering so I didn’t go very far underneath the truck to take these pics. I believe it’s a 4 speed with granny gear. I haven’t driven it much at all but will put some miles on it soon.
 

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bucket

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It's an SM465, with a 32 spline output and used a round pattern style t-case adapter with the short style mount. You also have the '85-up hydraulically actuated clutch.
 
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mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
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You’re amazing, thank you. Is the drive train acceptable for my rig? I mostly plan to use it on dirt and minimum maintenance roads; also considering putting a camper on the back of it for once or twice a month trips, probably less than a 100 miles round trip.

What’s involved to change the lube in both the transfer case and sm465? I’ve done differentials before.
 

bucket

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You have a great combination of drivetrain components, IMHO. Some people will complain about the 208 being an aluminum case and chain driven (like everything else in the last several decades), but they really are pretty good.

Changing the fluids is just like a differential, with a drain plug and a fill plug.
 

mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
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thank you for all the responses, good to know. This site is really motivating me to get started on the k20 restoration. I’ve done most all the work on all my GM vehicles over my lifetime and I have all the tools, it’s time which will be the challenge. I’m also still trying to finish up a 72 chevelle restoration but I’m close so I think I can at least start buying some interior parts so I can start there. Here’s a pic of my before and after chevelle.
 

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mxer147

83 K20, 350 vortec, 465, 208, 14/10, 4.10, 33s
Joined
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Jack
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1983
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k20
Engine Size
350
Bought the Malibu for $800 mostly because I wanted to reconnect with my Dad who passed about 5 years earlier. We use to work on cars together and I have all his tools. He was an auto bodyman and painter so I figured I would give it a try. The only parts original to the chevelle resto are the drivers fender, door, roof, pans, radiator support and frame; everything else was replaced with either new or quality used. It has a stroked 400 sbc, th350, 12 posi; I kept a modified ac and converted the interior to SS with buckets, console and gauges. It was a lot fun to build and sure was a lot of cussing doing the bodywork. Dad and I restored his Dad’s 73 C20 in 1984 which we replaced almost everything but the drivetrain and frame. I actually let that one go to the recycler along with a bunch of good body parts about six years ago mostly because I didn’t have a place to put it and it was really rusty again and had prolly 300K miles on it. I am kinda questioning that decision since I could probably use some of the interior and I also like the look of the single round headlights. Those square body trucks were everywhere seems not too long ago but really have become rare as of late. I don’t think I even have one picture of that 73, sad because it was mint after we restored it, interior, exterior, all of it. He always finished what he started and made it a point to teach me to not start something new until you finish what you’re working on or you usually end up with alot of unfinished projects….very good advice! He would also say “we can F**k it up just as easily as the next guy” to avoid paying for someone else to do your work….more good advice. Anyway, your 70 SS looks great! Here’s a couple more angles of my chevelle Malibu.
 

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idahovette

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@mxer147 is it an original white car and vinyl top? Ya done good! Mine was NOT and I had to rebuild it after I got it back for the 2nd go around
 
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