V-code spring upgrade questions
Super Moderator
Joined: May 2004
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From: Central Coast of CA
It took me around 3 or 4 hours, and my buddy did most of the work because I have a bad back.
I did the left side first then the right side. On the right side I had to unbolt the rear spring shackle from the frame because the the front drive shaft was in the way.
I lowered the antisubmarine bar and left it hanging on the rubber to get to the front spring bolts. Also to access the front spring bolt heads there are brackets that support the powersteering cooler, a 10mm bolt holds it in place, the 10mm bolt is hidden behind the rubber baffling. It is a lot of manual labor but well worth it in the end, enjoy!
4 bolts and it's out of the way.
Stewart
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Joined: Apr 2009
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From: Elmira New York
Probably about 5 hrs of actual work, another 2 farting around moving a couple of airplanes out of the hanger to make room, getting my tools sorted, lunch. The driveshaft slowed me down a bit.
Posting Guru
Joined: Oct 2003
Posts: 1,198
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From: Tulsa, OK
I also did "V" code springs to front axle this Saturday. Took me about 6 hours actual work. Totally working on my own. Had the same problem that when I disconnected the front hanger bolt on drivers side, the axle moved back almost 2". I think this is due to the twist on axle (from above) caused by track rod and steering linkage.
I was able to move the axle back forward (when installing new springs) by creative use of several 2x4s prying against the track rod frame mount. A come-along would have been much easier...
Now, I have a parts problem. What U-bolts should I get for the rear axle "B" spring upgrade? I cannot find a Ford part number anywhere in my search of this subject. Local Ford dealer parts dept. tried F-350 U-bolts on me, but they are for bigger diameter axle tube. Too big by about 3/8" in diameter.
Anyone know what Ford part number for rear axle U-bolts when putting 3.5" tapered block?
I was able to move the axle back forward (when installing new springs) by creative use of several 2x4s prying against the track rod frame mount. A come-along would have been much easier...
Now, I have a parts problem. What U-bolts should I get for the rear axle "B" spring upgrade? I cannot find a Ford part number anywhere in my search of this subject. Local Ford dealer parts dept. tried F-350 U-bolts on me, but they are for bigger diameter axle tube. Too big by about 3/8" in diameter.
Anyone know what Ford part number for rear axle U-bolts when putting 3.5" tapered block?
Super Moderator
Joined: May 2004
Posts: 29,380
Likes: 118
From: Central Coast of CA
Now, I have a parts problem. What U-bolts should I get for the rear axle "B" spring upgrade? I cannot find a Ford part number anywhere in my search of this subject. Local Ford dealer parts dept. tried F-350 U-bolts on me, but they are for bigger diameter axle tube. Too big by about 3/8" in diameter.
Anyone know what Ford part number for rear axle U-bolts when putting 3.5" tapered block?
Rear U-Bolts F81Z*5705*EA
Stewart
Tuned
Joined: Nov 2007
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From: SoCal
I just ordered those bolts myself - will check the part numbers when I get home...
Posting Guru
Joined: Oct 2003
Posts: 1,198
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From: Tulsa, OK
I'm also unsure of part number, but I don't think this one is for rear axle. Interestingly, the front axle U-bolts are almost (but not exactly) the same number.
Front axle U-bolts (I have these installed): F81Z*5705*ZA
I just returned from Ford dealer and he sold me a box of four (4) U-bolts also for an F-350 rear axle about 2004 vintage:
The package (probably because it is a set) has a completely different number: N80377-S436.
The 4 U-bolts in this box look like they will work. They have a length (center of circle to end-of-thread) of approx. 12". The original Excursion rear U-bolts were approx. 10.5" length. The inner diameter is approx. 3.75". Previous set they sold me had an inner diameter measured at 4.13"--way too big.
I will report tomorrow if this set of 4 U-bolts (N80377-S436) is correct for 3.5" tapered block install on "B" code springs, rear axle.
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Posting Guru
Joined: Oct 2003
Posts: 1,198
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From: Tulsa, OK
rkik--
I am only guessing, but I bet my part number (N80377-S436) is a set of four (4) of your part number (F81Z*5705*EA).
When I look at your installed picture, though, I have a concern. Your new U-bolts do not fit snugly to the axle tube. I measured the circumference of the axle tube (with a seamstress tape) and got 11-1/16". Dividing by PI, this calculates to a diameter of 3.52" (bet it is actually 3.50").
I measured the four (4) U-bolts I just purchased at Ford (N80377-S436). They have an inner diameter of 3.75", leaving a 0.13" gap on each side. When I look at your picture, you appear to have the same gap on each side of your new U-bolts.
Shouldn't the U-bolts fit tightly? Seems like you could dimple the axle tube if not the correct size(?).
Are F-350 axle tubes a different diameter than Excursion axle tubes? So far, I have been sold two (2) different U-bolts that are meant for the F-350. One was 4-1/8" ID and one is 3-3/4" ID, at least as far as I can tell. I bet one was for DRW axle and one for SRW axle. I don't think either is the same as Excursion rear axle tube. I also heard something about Dana and Visteon.
Can anyone answer these questions?
I am only guessing, but I bet my part number (N80377-S436) is a set of four (4) of your part number (F81Z*5705*EA).
When I look at your installed picture, though, I have a concern. Your new U-bolts do not fit snugly to the axle tube. I measured the circumference of the axle tube (with a seamstress tape) and got 11-1/16". Dividing by PI, this calculates to a diameter of 3.52" (bet it is actually 3.50").
I measured the four (4) U-bolts I just purchased at Ford (N80377-S436). They have an inner diameter of 3.75", leaving a 0.13" gap on each side. When I look at your picture, you appear to have the same gap on each side of your new U-bolts.
Shouldn't the U-bolts fit tightly? Seems like you could dimple the axle tube if not the correct size(?).
Are F-350 axle tubes a different diameter than Excursion axle tubes? So far, I have been sold two (2) different U-bolts that are meant for the F-350. One was 4-1/8" ID and one is 3-3/4" ID, at least as far as I can tell. I bet one was for DRW axle and one for SRW axle. I don't think either is the same as Excursion rear axle tube. I also heard something about Dana and Visteon.
Can anyone answer these questions?
Former Vendor
Joined: Jan 2006
Posts: 3,849
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From: Seattle
all depends on whether you have aux rear springs when adding the U-bolts for the blocks,
F350 W/AUX NARROW FRAME M16X2.0 X 108/343 PART NUMBER N803770S436
F350 W/AUX WIDE FRAME(RAISED OVER AXLE) M16-2.0 X 118/302 N811676S436
F350 W/O AUX WIDE FRAME M16X2.0 108/320 N811667S436
F350 W/O AUX WIDE FRAME M16-2.0 X 118-266 N811675S436 (DANA AXLE)
F81Z5705BA front w/ square seat
F81Z5705ZA FRONT w/ round seat
it get real fun real quick if you dont pay attenion looking at part numbers in the catalog.
F350 W/AUX NARROW FRAME M16X2.0 X 108/343 PART NUMBER N803770S436
F350 W/AUX WIDE FRAME(RAISED OVER AXLE) M16-2.0 X 118/302 N811676S436
F350 W/O AUX WIDE FRAME M16X2.0 108/320 N811667S436
F350 W/O AUX WIDE FRAME M16-2.0 X 118-266 N811675S436 (DANA AXLE)
F81Z5705BA front w/ square seat
F81Z5705ZA FRONT w/ round seat
it get real fun real quick if you dont pay attenion looking at part numbers in the catalog.
Posting Guru
Joined: Oct 2003
Posts: 1,198
Likes: 2
From: Tulsa, OK
all depends on whether you have aux rear springs when adding the U-bolts for the blocks,
F350 W/AUX NARROW FRAME M16X2.0 X 108/343 PART NUMBER N803770S436
F350 W/AUX WIDE FRAME(RAISED OVER AXLE) M16-2.0 X 118/302 N811676S436
F350 W/O AUX WIDE FRAME M16X2.0 108/320 N811667S436
F350 W/O AUX WIDE FRAME M16-2.0 X 118-266 N811675S436 (DANA AXLE)
F81Z5705BA front w/ square seat
F81Z5705ZA FRONT w/ round seat
it get real fun real quick if you dont pay attenion looking at part numbers in the catalog.
F350 W/AUX NARROW FRAME M16X2.0 X 108/343 PART NUMBER N803770S436
F350 W/AUX WIDE FRAME(RAISED OVER AXLE) M16-2.0 X 118/302 N811676S436
F350 W/O AUX WIDE FRAME M16X2.0 108/320 N811667S436
F350 W/O AUX WIDE FRAME M16-2.0 X 118-266 N811675S436 (DANA AXLE)
F81Z5705BA front w/ square seat
F81Z5705ZA FRONT w/ round seat
it get real fun real quick if you dont pay attenion looking at part numbers in the catalog.
Again, I think that the 108 mm is the nominal (centerline) diameter of the smaller U-bolt. If 16 mm is the thread pitch outer diameter, that would mean the U-bolt I.D. would be slightly larger than (108 - 16) mm = 92 mm = 3.62". I measure approximately 3.75". I think the difference (0.13") is the height of the threads.
This really implies to me that none of the F-350 axle tubes are same O.D. as the Excursion axle tubes (I measure mine at 3.50"). I am also guessing that this may only be academic--It may not matter. Several people have been using these U-bolts to put the rear spring assembly together. rkik shows it in his pictures. Have to assume it is OK to do this(?).
Am I worried about anything important here?
Posting Guru
Joined: Oct 2003
Posts: 1,198
Likes: 2
From: Tulsa, OK
I installed my "B" code rear springs last night. The rear U-bolts (M16X2.0 X 108/343 PART NUMBER N803770S436) fit the Excursion rear axle tube just fine, with only about 1/32" clearance on front/back side of tube. With the 3.5" tapered block, you have about 2" of bolt sticking out above the nuts. This seems like it will be OK.