Difficulties installing & torquing rear drum - Help!

[psogden]

Hi guys & gals. Read every Ford Barn post I could find on the subject, Dick Flynn tips, etc. before starting to torque the 5/8 – 18 axle nut and found out the conventional wisdom is a final torque of 200- 225 foot pounds. Proceeded very cautiously inching the nut on and carefully measuring every 10 or 15 foot pounds. When I got to 175 the nut failed. The nut, by the way, was purchased from a well known reputable Old Ford V-8 parts vendor. I took it down to my local NAPA parts house to see if I could get a replacement. All they had in stock was a non-castellated variety (not surprisingly). They guy behind the counter felt that my nut was not a Grade 8 quality and, given my experience, I am inclined to agree which makes me wonder about the reliability of the folks that sold me the nut. I purchased a non castellated Grade 8 nut from NAPA and ran it on to the axle to see what would happen. Unfortunately it stopped before it reached the drum. So, I removed it and checked the axle threads which seem to be ok. So, should I run a 5/8 -18 dye over the threads to clean them up—or am I looking an axle replacement? And where do a get a Grade 8 castellated nut? Finally, do I really need to torque to 225 foot pounds? That seems like a lot.

[Charlie Stephens]

Be sure to get back to the supplier that sold you the original nuts and see what they say. Let us know how it comes out. Give them some advertising, good or bad.

Charlie Stephens

[JSeery]

I would check with Roy and see what he has (assuming he's not who sold you the original one!!)

[Bluebell]

Is there supposed to be a thick washer between the nut and the drum?
What do you see is wrong with the thread?
If that is the recommended torque then that is what I'd do.
You may not understand this because I cannot think how to explain it. The hub climbs the taper on the axle and holds on the clean taper. It should actually work (drive) without the key (But of course you always use the key) This clamping effect is a result of that nut going up to torque. If the hub is not tight on the axle the two mating surfaces will "fret" damaging both.
Someone will direct you to a supplier (Mac VanPelt?) If not, Buy a grade 8 deep nut and have it slotted

[GEOFFNZ]

seems like an awful lot of torque considering age and possible condition of axle threads.I would have thought 175 would achieve a reasonable result. Cheers

[Kurt in NJ]

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Original nuts were case hardened, nowadays would be more than grade 8----try taking a file to an original nut--it won't hardly scratch it

[flatheadfan]

Sounds like a thread problem. If it is, you only have two choices, re-thread or replace. To re-thread don't use a normal 5/8-18" threadchaser or die. What you need is an axle threader (note picture). This starts the re-threading in the center of thread travel not on the end where a die can go on crooked. As for nuts, I got two recently from Joe's Auto and they went on a '36 without a problem at 200+ pounds.

Hope this helps.

Tom

[Planojc]

In the Model A world most torque to 100 foot pounds so why 200 on the V8's ?

[JM 35 Sedan]

Originally Posted by psogden

Hi guys & gals. Read every Ford Barn post I could find on the subject, Dick Flynn tips, etc. before starting to torque the 5/8 – 18 axle nut and found out the conventional wisdom is a final torque of 200- 225 foot pounds. Proceeded very cautiously inching the nut on and carefully measuring every 10 or 15 foot pounds. When I got to 175 the nut failed. The nut, by the way, was purchased from a well known reputable Old Ford V-8 parts vendor. I took it down to my local NAPA parts house to see if I could get a replacement. All they had in stock was a non-castellated variety (not surprisingly). They guy behind the counter felt that my nut was not a Grade 8 quality and, given my experience, I am inclined to agree which makes me wonder about the reliability of the folks that sold me the nut. I purchased a non castellated Grade 8 nut from NAPA and ran it on to the axle to see what would happen. Unfortunately it stopped before it reached the drum. So, I removed it and checked the axle threads which seem to be ok. So, should I run a 5/8 -18 dye over the threads to clean them up—or am I looking an axle replacement? And where do a get a Grade 8 castellated nut? Finally, do I really need to torque to 225 foot pounds? That seems like a lot.

Can you post a close up picture or two that would show us the condition of the axel threads? Also, if you send me an email using the Fordbarn system I can get back to you tonight with some info that might be of some help to you.

[V12Bill]

I put on axle nuts to 150 ft/lb and then tighten until the castleated nut lines up with the hole in the axle. by the time I have done this , I am sure that I am in the neighborhood of 200 + ft/lb.

[Gary in La.]

Many venders are showing in their illustrations nuts that don't appear at all like the originals. The original Ford nuts besides being hardened are a full 3/4" long and the same diameter full length with no tapering at the slots. These are the must save items even when scrapping out a scrap rear end.

[psogden]

Thanks for all the replies. I'll see what happens & give an update later. Be away for a few days--so probably next week sometime.

[JSeery]

I would think used original axle nuts would be easy to come by.

[Charlie Stephens]

No mater what the outcome you should run safety hubs or safety clips. You can get these four hydraulic brakes but unfortunately not for mechanical brakes.

Charlie Stephens

[DavidG]

With respect, only '33 and up axle nuts are slotted hex nuts while those used during the '32 model year and earlier were castle nuts (which taper at the slots).

[Bassman/NZ]

I have tried new nuts and found them wanting. Best course is to find originals.

[Mart]

I like those original nuts that were a bigger hex size. I had just the one on a 40. I'm not sure which years they came on though. Standard hex size is 15/16" for a 5/8 nut, there are bigger, something like 1-1/16" (guessing here). Like mentioned above, saving the original nuts is a must. That said I have used aircraft quality self locking nuts (Philidas brand) on my roadster and I like those.

Mart.

[psogden]

Before departing on a short trip for a few days (and getting back to the reality of the problem at hand) did some checking to satisfy my curiosity.

Here is part of a Ford Barn post from “Kens 36” dated 4-19-11: “A mailgram dated 10-20-47 (from the Ford Archives) detailed the procedure for assembling the hub and drum to the axle shaft. It specified use of a 24 inch handle and a torque of 300-350 foot-pounds. Service Letter A-25 dated 11-6-47 corrected the torque setting, stating: “tighten nut 356074-S to 200-220 foot pounds; then continue to the next castellation providing final resultant torque does not exceed 275 foot pounds.”

I then consulted (former and deceased) Ford V-8 Times great repair guru Dick Flynn’s article on the subject. Here is his recommendation. “Torque nut to 150-160 ft. lbs. of torque. The axle metal is grade 8 or better, 5/8-inch grade 8 bolt torque is 225 ft. lbs. So we aren’t even close to that."

So, obviously there is considerable discrepancy here. But 220 would appear to be pushing the outer limits if Flynn is correct.

[JM 35 Sedan]

Originally Posted by psogden

Before departing on a short trip for a few days (and getting back to the reality of the problem at hand) did some checking to satisfy my curiosity.

Here is part of a Ford Barn post from “Kens 36” dated 4-19-11: “A mailgram dated 10-20-47 (from the Ford Archives) detailed the procedure for assembling the hub and drum to the axle shaft. It specified use of a 24 inch handle and a torque of 300-350 foot-pounds. Service Letter A-25 dated 11-6-47 corrected the torque setting, stating: “tighten nut 356074-S to 200-220 foot pounds; then continue to the next castellation providing final resultant torque does not exceed 275 foot pounds.”

I then consulted (former and deceased) Ford V-8 Times great repair guru Dick Flynn’s article on the subject. Here is his recommendation. “Torque nut to 150-160 ft. lbs. of torque. The axle metal is grade 8 or better, 5/8-inch grade 8 bolt torque is 225 ft. lbs. So we aren’t even close to that."

So, obviously there is considerable discrepancy here. But 220 would appear to be pushing the outer limits if Flynn is correct.

psogden, I just sent you a pm on this, so it's probably not necessary to repeat all that I said there, but here is information on the subject of torquing early Ford axle nuts, that I just copied from the 32 to 53 Flathead Ford Techno Site.....

"Posted by Nirvana June 13, 2002 at 7:19PM :

I hate these senior moments!! I can't find my book with torque value of the axle nuts on a 40 stock rear end. 180 Lbs keeps ringing in the back of my emptyness, is this the correct value??

Thanks, might take her out for a spin this week-end after 3 years, if the wheels don't fall off first.

Posted by JWL June 13, 2002 at 8:32PM :

In Reply to: Torque value of axle nut posted by Nirvana from swd-pm1-007.inetnebr.com (209.50.13.147) on Thursday, June 13, 2002 at 7:19PM :

180 is on the low side, but will get you started before retorqing after the first drive. I use 220 and retorque weekly, on a rebuild, untill they stop moving. The spec sheets have varying values assigned to this connection.

Posted by FlatV8*June 13, 2002 at 11:49PM :

In Reply to: Re: Torque value of axle nut posted by JWL from 02-ocil-01f.dial.optilinkcomm.net (216.128.152.157) on Thursday, June 13, 2002 at 8:32PM :

The 'V8 Times', Sept/Oct 98 Issue, pages 46 and 48, quotes several Ford Service Letters and later corrections.
The final direction on tightening axle nuts reads: "tighten nut 356074-S to 200 to 220 foot pounds; then continue tightening to the next castellation providing final resultant torque does not exceed 275 foot pounds "

In my humble opinion, I would follow these specifications before I would consider the other torque specs you have posted above.

[psogden]

Am attaching a photo of the end of the axle where the threads on the 5/8 -18 failed at around 160 foot-pounds. I have removed the 5/8” washer to expose the edge of the drum. As you can see, (bit a bullet) there are still good threads on the axle. This would appear to confirm that the bolt was not a Grade 8 quality or it would not have failed. I do notice that the end of the key way on the axle is showing (right side of axle). Should the key way be exposed? Is it possible that the drum is on too far? If I understand the theory of the drum to axle fit, seemingly it would be impossible to torque the drum on too far. Am I correct or--??