Rear Brake Drums

[Gary Lewis]

That's his English cousin that uses Whitworth wrenches.  I think the guy that worked on Big Blue was Jacques Legg, and he's used to working on French vehicles.

[85lebaront2]

By jove, sir I have a set of Whitworth, or maybe English Standard combination wrenches, I'll have to look at the designation for sizing. Remember when using same, to "take spanner twixt thumb and forefinger" in order to properly use them.

Reading a British workshop manual is quite interesting.

[grumpin]

They're polite I assume.

They offer up parts for install, don't just slap them on!

[85lebaront2]

One must be cautious to obtain the correct silencer so as to prevent exhaust titter. The preceding from one of the first V8 Rolls-Royce workshop manuals. Another gem was from my sister's 1959 MGA workshop manual, commenting that later cars were equipt with (I forget the number designation) Lucas distributor which is fitted with a pre-tilted breaker plate. I guess this was to properly supply the high tension wires to the sparking plugs.

You haven't really appreciated England's refusal to be rushed into things until you have done the rear brake rods on a 1952 Bentley, yes, they still had mechanical rear drum brakes in 1952, the fronts were hydraulic, 1940 Ford wheel cylinders. Rears were a mechanical power assist system by a friction clutch on the gearbox driven by the output shaft.

Considering our 1953 Chrysler Custom Imperial had power steering and power hydraulic brakes, a semi-automatic transmission and a 331 Hemi, the Bentley was an anachronism. F head in-line 6, manual 4 speed transmission, manual steering and power assisted mechanical rear wheel brakes, manual hydraulic front brakes.

[grumpin]

Wow!

Someone once told me, Lucas, "the inventors of darkness"!

[Gary Lewis]

Grumpin - I think the term is "Prince Of Darkness".  That's 'cause the electrics tended to go out at the worst possible time.

Bill - Don't get me started.  Especially since we have Brits, and Brit ex-pats, as members.  But, having lived there, .....

[baddog8it]

Mystery partially solved.  I've confirmed that I have the Dana 70 rear end.  I gathered that by the tag info as well as the axle tube diameter.  The diameter for the 70 is published as 3-1/2" (mine measured 3-9/16 - lots of rust?).  The diameter for a D60 is 3-1/8".  The diameter for a 70HD is 4".

I'm seriously debating putting disc brakes on the rear end.  Seems pretty easy and not expensive.  Upside is that they brake better, are more reliable and if only replacing pads - can be maintained without pulling the axle.  The kits are readily available, or you can piece it together yourself and just buy the mounting bracket. Downside is that if I want a mechanical parking brake, it adds $150+ to the cost (the calipers come from mid 70s era Cadillac Eldorado.

There is still one mystery on my mind.  The differential casting should have a model number on it, which I would assume to be "70", but it appears to be "NC".  Any thoughts?

I also realized that there appears to be another metal tag at the very top of the differential.  I'll have to wait until the next time I drop the spare tire to check that one out.

Per the Dana manual, it is saying that the rear end on my truck only got put on chassis models.  I really need to get my hands on the build sheet.

[ArdWrknTrk]

A C&C truck will have straight rear frame rails, 2 1/2" wide springs and a frame width of 34". (gets narrower behind the cab)

Has the bed on your truck been redrilled about 2" narrower per side?

I have a hard time imagining someone going to the trouble of moving/swapping/welding spring perches and shock mounts to get a 70 beneath a pickup, when the 60 will carry more than the frame, or any of the rest of the truck, is rated for.
Then there's the pinion yoke and driveshaft.


I may be wrong... It wouldn't be the first time.

This sounds like a Q for Diesel Brad

[Gary Lewis]

You can find the chassis dimensions in the 1985 Body Builder's book: Literature/1985 Literature/Body Builder's.  Perhaps with that you can figure out what you have.

[ArdWrknTrk]

Yes, it would be interesting to know exactly what the wheelbase is on this truck.

[85lebaront2]

Jim, that shot of the cover with the interesting brake line routing makes me wonder. It could be that someone swapped in a 1980-1984 rear, or if the truck was an early production 1985 it could have still had the Dana in it. I don't know, maybe someone has the information if there is a "before" and "after" date on the rear axles in 1985. There were so many running changes in Ford trucks 1980-1996/7 that it gets interesting.

It wouldn't be the first time Ford did running updates, my 1964 Falcon with the 260 V8 and three speed column shift was built July 27th 1964 and had a lot of anomalies like 289 heads, Mustang PNs (C5ZZ-) on the instruments, larger lower ball joints, tie rod ends etc. break date was June 10th I think on a lot of it.

[ArdWrknTrk]

The Ford/Sterling 10.25 is generally accepted as '85 1/2 model year.
Another running change.

What a that means as far as production dates go and which plants were using up NOS I have no idea.
The fill plug is definitely Dana.

60 v/s 70 should be easy from the spring perches and pinion yoke, but again 'I've been wrong before'

[Gary Lewis]

I've not seen anything in any of the documentation that shows when the change was made.  And the date changes aren't accurate as it appears to me that each plant changed when they ran out of a given part since Ford threw nothing away.

Something I've seen lately for changes is "chassis #".  When I ordered the front wheel bearings from Amazon recently they said they were the right ones "from chassis # XYZ".  But, I couldn't correlate their # to anything on Dad's truck.  

[Ford F834]

It sounds like you have been doing your homework on the disc brake conversions... but I wanted to throw in that there are some not so good reviews on using the El Dorado calipers to gain the parking brake function. I am only repeating things I’ve read, but it was enough to steer me in other directions. Many report that they just don’t brake as well as they should. I’m not exactly sure why, but one guy reported that switching to the non-parking brake Chevy pickup caliper made a huge improvement. Because of the parking brake element, they are not “floating” and do not self adjust. For those hoping to get away from fiddley rear brake adjustments, prepare for disappointment. I hear they are touchy and need to be adjusted frequently. Now in your case, I think I would do just about anything to rid myself of inboard mounted drums. The drawbacks/risks may be worth it. However, I would investigate the possibility of a driveline parking brake, or dual caliper brackets (if available for the D70) that will mount a hydraulic caliper for braking and a mechanical caliper for parking. Another thing that guys do is install a hydraulic line lock that holds fluid pressure to the rear brakes. This functions well, but won’t pass safety inspections. It is not a mechanical back-up, and if it releases... 😬😬😬. Another option is an axle swap. It sounds drastic, but in my junkyards the price of a complete rear axle was $125 plus $20 core charge. I can’t speculate about your local parts market, but it’s just something to think about. Rear disc conversions can start out cheap, but end up pricey depending on what all you do about the parking brake. I have the Sterling, and decided to stay with drums for the time being... but I may revisit the rear disc idea later on. I had to switch axles because of a bad pinion bearing, and my new axle had good brakes so it’s a bit hard to justify changing.

[85lebaront2]

FWIW, the E-series have rear disc brakes with internal drum parking brakes. A good friend has a 2003 E250 with the 4 wheel disc brakes. I am pretty sure he has the Sterling under it and for an SRW it should work, 8 bolt pattern, but don't know if it is the same or metric.

[Ford F834]

There were rear disc Dana axles under Econoline E250/E350 vans that held the SAE bolt pattern later than the trucks (1999-2004?). It is a good axle swap to gain rear disc, but the spring perches need to be moved for the truck frame width. Seems like there were a couple other small modifications needed. It takes a little doing but is a good upgrade.

[ArdWrknTrk]

I think the van track (width, flange to flange) was a little narrower as well.

We all know these trucks are already a little narrower in the rear than front.

Not sure how much it matters, but something to note anyway.

[85lebaront2]

I wasn't thinking about the whole axle, just the brake parts, particularly if the disc/drum portion slides off.

[ArdWrknTrk]

You say your friend has a van with a Sterling but we are obviously looking at a Dana.
Would they interchange?

I know nothing about disc brake Dana's. Are their rotors trapped by the axles?
Seems a pita for brake service. At least you can be assured the diff fluid gets changed on the regular.

[85lebaront2]

I believe the van brakes as complete units would. I am reasonable sure it is a Sterling, but it could be a Dana, I have not had the rear apart on it.