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I have an original 1977 F-250 4x4 chassis manual that I use whenever I setup a diff. I don't do it often enough to remember what to do. The pictures and descriptions in the old Ford manual are great.

Just by looking at it the pattern doesn't look perfect to me. I bet it would run great, but you can do better if you tweak it in and you might as well.

Also, this is just a small thing, but you don't need to and may be making things harder by painting the gear teeth with spotting ink like that.

I come from a machining background where we hand scrape and fit things to very high accuracy. It's called "making a print", "printing" or "spotting" when you use a spotting ink to get a visual of how two surfaces interact. What you want is a thin, even coat. Too thick can actually make things look a way they are not.

The ink I use is way too thick to do anything useful with from the bottle, it must be thinned a bit. Windex is the best thinner for the Cannode ink I use.

You're doing great though. Make sure you use a ton of carrier preload when you get there. I'm 265 LBS and if I can barely get it in with a 5 lb deadblow it's just right.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #62 ·
Question on this gear pattern in the pictures. Went to repeat it using the same shim settings, but backlash was way out (first time was .005” second was .013”).

Seems as though whenever I find a centered gear pattern, backlash is way high and sloppy. Then, When I move the ring gear closer to pinion (as the manual and everyone says to do...) backlash gets better but pattern moves to centered closer to toe.

What’s going on here? How do you guys ‘fix higher backlash and keep the pattern centered?
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #64 · (Edited)
Not using a spreader. Torquing caps to 80. Original open diff, new bearings.

Original 3.55 spicer, Looking for RP wear, don’t see indented teeth, chips, ridges, or anything, unless the wear is uniform to the extent that each tooth profile is consistent and smooth.

Taking multiple BL measurements each time and am trying to reduce backlash with less pinion depth (more IP shim) sound like a good idea?

I completely identify with this process being a meticulous labor intensive. Visualizing the geometrical aspect helps some but there is still by guess and by golly.

Reading billavista a 3rd or 4th time is a help.


Are these used or new gears? If new, what brand?
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #65 ·
Over to the engine, Going to install injection pump following cummins shop manual directions. Will work slow and check everything. Tag says "PUMP IS LOCKED."

Anyone have wisdom to share?

I timed TDC/set timing pin using the piece of metal bolted to cylinder method described in the manual. Will take #1 valve cover off to insure compression stroke.

Pump return bolt has this one tiny hole, assuming this is correct. Seems a bit undersized.

View attachment 132680
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #66 ·
Snuggletough, I am hard headed and am not winning this battle setting a pattern with proper backlash. Going to spend the $180 and put a new set of gears on. Here we go, hopefully the same scenario doesn't happen with new gears. Found Dana/Spicer India made 'SVL' 10001732 3.55 reverse rotation gears that are about 2 weeks away using summit.

Are these used or new gears? If new, what brand?
 

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Snuggletough, I am hard headed and am not winning this battle setting a pattern with proper backlash. Going to spend the $180 and put a new set of gears on. Here we go, hopefully the same scenario doesn't happen with new gears. Found Dana/Spicer India made 'SVL' 10001732 3.55 reverse rotation gears that are about 2 weeks away using summit.
The reason I asked the question is aftermarket gears are a crapshoot and if the OEM gears were run for 40 years with excess backlash then that's where they are going to print well. If they look good with a bit extra lash then run them there. It's a front axle.

I would buy a $40 timing tool on Amazon and actually set your timing. Then you can set it to a specific value and actually know where it is and get it back the same if you take it off or swap pumps.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #69 ·
Got it on gears. The Dana44 in there now had been running old gears that whine at higher speeds. I appreciate your comments on this project!

The front leaf springs bracket is mangled and patched up from the previous owner's use on a ranch in the sandhills of Nebraska. Figured as long as that 'needs' replaced, going to try the Battle Born Brakes front springs bracket which uses 1999-2004 super duty springs. Ride quality/sag are the benefit while keeping the stock height. I'm not into the bling of lifting, I suppose my thing is form follows function - rugged originality is attractive to my taste. 👍

Ford Highboy Front Leaf Spring Bracket 1967-77 F250 4wd | Battle Born Brakes

This bracket and front-rear shackles has the front spring eye moved down and farther forward to keep the axle centered and the spring's military wrap from needing cut off. Having shackle tabs welded on the front. Probably going to try stock SD 2630LB springs.

Wood Hood Hardwood Wood stain Auto part
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #70 ·
Bosch VE pump installed. Followed the manual's directions. Gear aligned at letter F with 0. A while back I timed the timing pin using the cummins method of strapping metal to the block head and then finding the center. Took off #1 valve cover, noted no tention on intake/exhaust for compression stroke. Cleaned everything off and everything went right in.

Gear cover gasket and front seal installed, sealed up.

Got the pump bracket painted and PS support bracket ready.

Against Peter Gould's (Gould Gear who rebuilds the vacuum pump portion) advice, running the Borgeson dodge PS pump. I have a borgeson on the FE390 that works great, no complaints. Didn't want autozone or high performance that require coolers, etc.

Automotive tire Motor vehicle Automotive design Bumper Automotive exterior


Made studs from threaded rod, used lock washers. Installed using blue loctite.

Nice to check a few items off the list now that the weather is colder!
 

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Got it on gears. The Dana44 in there now had been running old gears that whine at higher speeds. I appreciate your comments on this project!

The front leaf springs bracket is mangled and patched up from the previous owner's use on a ranch in the sandhills of Nebraska. Figured as long as that 'needs' replaced, going to try the Battle Born Brakes front springs bracket which uses 1999-2004 super duty springs. Ride quality/sag are the benefit while keeping the stock height. I'm not into the bling of lifting, I suppose my thing is form follows function - rugged originality is attractive to my taste. 👍

Ford Highboy Front Leaf Spring Bracket 1967-77 F250 4wd | Battle Born Brakes

This bracket and front-rear shackles has the front spring eye moved down and farther forward to keep the axle centered and the spring's military wrap from needing cut off. Having shackle tabs welded on the front. Probably going to try stock SD 2630LB springs.

View attachment 132695
I built that same crossmember from 3x4 3/8" thick angle about 20 years ago on my highboy. Iirc, Superduty springs are about 2" less lift on a highboy than they are on a Superduty. 2" springs would be stock, 6" would be 4", etc.

The thing about Highboys is the ride height depends on the GVW. If the truck had the big front hubs and overload springs in the rear it is the 8800 GVW truck and it actually sits way up there. The standard GVW highboy with the baby knuckle 44 front and no overload brackets riveted to the frame sits much, much lower.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #72 ·
Thank you for the tips on SD spring height - this will help to figure the appropriate set to find. I talked to Jacob at BBB, he said find the stock springs and go 500 lbs higher, snowplow springs, don’t get too heavy duty.

My truck originally came with the big ball 12bolt wiper knuckle front axle big hubs, HD option.

I built that same crossmember from 3x4 3/8" thick angle about 20 years ago on my highboy. Iirc, Superduty springs are about 2" less lift on a highboy than they are on a Superduty. 2" springs would be stock, 6" would be 4", etc.

The thing about Highboys is the ride height depends on the GVW. If the truck had the big front hubs and overload springs in the rear it is the 8800 GVW truck and it actually sits way up there. The standard GVW highboy with the baby knuckle 44 front and no overload brackets riveted to the frame sits much, much lower.
I took some scrap to the metal yard the other day and here’s what the scale said with an empty bed but my bag of bones:

Sky Cloud Automotive tire Mode of transport Motor vehicle
 

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That is going to be one sweet Bump when you are done! I also used the super duty springs in my ‘97. In my opinion, even the code “U” set is a bit stiff under the 4bt, and my truck is an extended cab. I think they are rated for 2,030 per side.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #75 ·
Thanks Levis for your experiential information on the SD 2030lb springs. Want to avoid the buying trying buying trying method because that gets expensive. So I’ll have to read into it and gaze into the crystal ball to find the right length and weight rating. Stock HD 2200 lb are in there now.

How did you chose yours?
 

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I will admit, it was rather arbitrary. If I had it to do over, I would call ATS spring in Pa. they have helped with a lot of super duty spring and RSK conversions and could probably get you exactly what you need
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #77 ·
Thanks Levis for the springs supplier information. Always good to talk to people who are in the know about conversions and are not just schlepping parts.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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Discussion Starter · #78 ·
Time to maybe fix wasn't broke??:eek:

Was reading a few builds about piston protrusion / head gasket thickness. Second guessed my decision to run stock gasket without measuring piston protrusion, figured now would be a good time. Didn't want to get into a pickle on the road someday, have a lot of $$/time in and this would be cheap insurance purchasing the right size head gasket.

When stock head gasket was installed the late 80's shop manual didn't have information on protrusion and block didn't need decked (straightedge/feeler gauge verified) with then original pistons. Was guessing it'd never been decked, no X on the side of the block.

I have a dial indicator mounted on a piece of maple with three bolts I use to set cutterheads on the wood working jointer. Quickserve says to take measurement over pin but I also took some over driver/passenger side rocking piston slightly to get a max reading at their TDC's.

Human body Slope Font Triangle Rectangle


Max protrusions Front/Rear and Driver/Passenger piston sides:
#1 .032 .033
#2 .027 .025
#3 .032 .035
#4 .028 .025

Automotive tire Bicycle part Rim Automotive engine gasket Audio equipment


Checked and verified, clearly the overall protrusion is at/over the MAX of .028. I guess it was broke!? o_O

Would a .25MM (.010") over thickness gasket be correct? Would it also be correct with .5MM overbore cylinders/pistons?
 

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Stpackard, on your power steering/vacuum pump combo be sure you install the support brace. Without it the wings on the vacuum are likely to break. That standard VE injection pump brace is part 3905313. It is the same for a 4bt or 6bt without the vacuum pump. See 1st photo below. The one for the 6bt with the vacuum pump is part 3918949 shown in the 2nd photo. That one has the vacuum pump brace attached but it is a separate part number 3919619 shown in the 3rd photo.
 

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1972 F250 4x4, 78 d60/d60, 3.55, np205, 200hp 4bt nv4500
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187 Posts
Discussion Starter · #80 ·
Thanks again Char1355, I’m perplexed all those rotating parts are bolted on to the aluminum gear housing so it’s good there’s the bracketry to reinforce. Those two brackets were pricey items but good to know they’re there so that parts aren’t flapping in the breeze.
 
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