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| | | Forums66 Topics128,092 Posts1,056,457 Members48,443 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Feb 2015 Posts: 273 Shop Shark | | Shop Shark Joined: Feb 2015 Posts: 273 | 1953 3800 Flat Bed Dually So, I'm doing a 14 bolt swap and I'm at the point where I would set the pinion angle and weld it up. But, I'm also going to be swapping in a 250 I-6 in place of the 216 and keeping the SM420 4 spd. When I do the engine swap, I'll be removing the '53 crossmember under the engine and swapping in a '54 crossmember and a 60's truck bellhousing so the rear engine mounts will be a bolt in. The front (side) engine mounts will will likely be the tubular crossmember mount offered in many places. That being said, I was thinking it may be wise to just bolt the rearend up (not super tight) and leave the pinion angle setting and the welding until after the engine is in place and done. Agree? Disagree? The 3800 has 2 drive shafts and a center bearing, so if the trans angle changes, I may have to adjust the center bearing "height", for lack of a better word, to get the drive angles correct. I would think welding in the rearend might not be wise just yet. I am using this document for reference. https://www.dropbox.com/s/btgxn9qt992vx3x/J3311-1-HVTSS.PDF?dl=0Specifically, the section on "Multiple Shaft Installations". Larry W.
1953 3800 Dually Flatbed
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Good idea, the pinion angle should be set with the truck in the loaded position. If going with 250, why not a 292?
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2015 Posts: 273 Shop Shark | | Shop Shark Joined: Feb 2015 Posts: 273 | Availablity, price, and the offset motor mounts would have prevented using the tubular crossmember style side mounts I planned on.
Basically, I came across a totally dressed, running 250 and it is double the horsepower of the 216. It came with carburetor, HEI, alternator, power steering bracket and pump, for $300.00.
Larry W.
1953 3800 Dually Flatbed
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | I agree, the best practice is to wait and set the pinion angle when the truck is as complete as you can get it. When you get to that point here is all the info you need on driveline setup and angles. http://www.stovebolt.com/techtips/driveline/setup/index.html | | | | | Joined: Feb 2015 Posts: 273 Shop Shark | | Shop Shark Joined: Feb 2015 Posts: 273 | Hey Grigg,
Thanks buddy. I'll store a link to that for later.
Once I get the engine and trans back in place, I figured I would throw the spare 14 bolt on the back of the frame rails so I set it when mildly loaded.
Larry W.
1953 3800 Dually Flatbed
| | | | | Joined: Apr 2009 Posts: 187 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 187 | Just going through a new steady bearing setup with a two piece shaft so your links have been helpful. I just had a new topic about a mystery steady bearing, so I've given up trying to find the same bracket replacement and using a newer style bearing but have to set up a new mounting bracket to achieve the best angle
I would rather be late 10 minutes in this life than 10 minutes early for the next
The reason my lady and I have been together so long is because of the kids. Neither one of us wanted sole custody | | | | | Joined: Feb 2015 Posts: 273 Shop Shark | | Shop Shark Joined: Feb 2015 Posts: 273 | Steady bearing...not familiar. Same as carrier bearing at midpoint of the shafts?
Larry W.
1953 3800 Dually Flatbed
| | | | | Joined: Apr 2009 Posts: 187 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 187 | yes Carrier bearing would be considered the book term, but locally some people might say 'shaft steady bearing or shaft support bearing' depending on the application as you might have a bearing at each end of a shaft. I came from a marine environment which maybe how the term slipped
I would rather be late 10 minutes in this life than 10 minutes early for the next
The reason my lady and I have been together so long is because of the kids. Neither one of us wanted sole custody | | | | | Joined: Feb 2015 Posts: 273 Shop Shark | | Shop Shark Joined: Feb 2015 Posts: 273 | Gotcha. 
1953 3800 Dually Flatbed
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