You mileage is pretty good! I now wish I had gone that way with mine.....

I am going to install power assist steering and since I'm going to have a continuous running hydraulic pump, I'm planning to get a hydraulic assist brake booster system and use a dual reservoir.




Part of the reason to change it is, I also want to have a "split" brake system. I really want to have *some* redundancy so if I develop a leak, I don't completely lose the brakes...



Have you thought about going to a dual "res" system?

 

[QUOTE=HT32BSX115;8171429]
]
Have you thought about going to a dual "res" system?

Yes I was going to try a duel res. master cyl.
and a second hydrovac unit that I have but ran into problems getting the push rod lined up with the master cyl. So I put the stock brake set up together so I could get the truck running. I plan on looking into the split system again at later date.

 

If my memory serves my correct Isnt Thunderbird hood scoops the same. I
see them all the time and they are very close. All my trucks have them
but they are from Super Dutys from the sixtys due to all have 391FT with
that air cleaner set up. Also the rear end? Wouldnt one of those awful
looking Diesel Box trucks, they look like a television with wheels work. They
seem to aways pass me like 75mph. The wheel bolt patten looks real close
to a F600. sam

 

Also the rear end? Wouldnt one of those awful
looking Diesel Box trucks, they look like a television with wheels work. They
seem to aways pass me like 75mph. The wheel bolt patten looks real close
to a F600. sam[/QUOTE]

Yes the large 6 lug bolt pattern is the same. I am using a dana 80 out of a 90's freightliner mt 45 step van with a 3.31 ratio, I bolted up my stock 9r22.5 tires and wheels. I'm very happy with the swap.

 

Mileage update..... speedo was broken, bought a rebuilt on on epay
17.8 mpg combo city/hwy driving

 

I think the words "chevy" and "nice" don't actually go together.

 

Good Point!!!

 

Update for skzuk

 

I tried to reply via the link in the email you sent me via FTE. However, it wouldn't allow me that privilege. Fortunately your email address was in a half-tone typeface on the from line of your message. Evidently that isn't a valid address because my attempt to email to you bounced.

I've read many of your posts, and am greatly interested in the conversion: I am thinking of building a F600 with Cummins and a 5 speed Allison OD automatic to pull my 12180 lbs. (wet) 5th wheel and/or car trailer. Bear in mind I am not knocking your truck, I just want to brainstorm a bit and learn something.

1) You used the Dana 80 with disc brakes, 6 x 8.75 bolt circle, from a
FedEx truck (99 Freightliner MT 45 step van). Have you converted the front
bakes to disc? If so, did you use another axle, or swap spindles and hubs?
If you converted the front axle and/or brakes , what was your source vehicle?

I've been told that mid 80s F600 trucks have the same 34" frame width as the 56 F500/F600 and the axles can be swapped into the earlier truck chassis. Usually one sees disc brakes in front and drums in the rear (or disc on all 4 corners) - not the other way around...

2) Your Dana 80 has a 3.31:1 gear ratio and you're achieving 62 mph in 6th gear from a Fuller fs5306 6 speed non o/d trans @ 1800 rpm, with stock 9r22.5 Michelin tires and wheels. Does one really need the 4 speed Spicer 6041 aux trans with 15% overdrive? I allow you may want the under-drive ratios...

Seems like you're at optimum rpm for 62 mph, especially since OD in the aux box only drops your engine speed by 500 revs. 3rd in the aux trans is 3.31, or direct drive (same as the rear end ratio you have), and 4th is 2.86 for a .86 OD.

3) You stated the best donor for the 53-56 would be a late 90's Freightliner MT45 (step van/tool truck) because it has the Cummins engine with starter on the passenger side (if the starter is on the driver's side it will hit your steering box), and a Dana 80 rear end with the 6 hole bud wheels. Do these trucks come with manual trans or a Allison automatic? What about using the donor's front axle, or disc brake setup, in a F600?

4) Can the 6bt Cummins be fitted into a C600 without major surgery?

Thanks for your help and any input you can give me will be greatly appreciated.

John

 

[QUOTE=JohnRoss

1) You used the Dana 80 with disc brakes, 6 x 8.75 bolt circle, from a
FedEx truck (99 Freightliner MT 45 step van). Have you converted the front
bakes to disc? If so, did you use another axle, or swap spindles and hubs?
If you converted the front axle and/or brakes , what was your source vehicle?

Still using the stock drum brakes in front.

I've been told that mid 80s F600 trucks have the same 34" frame width as the 56 F500/F600 and the axles can be swapped into the earlier truck chassis. Usually one sees disc brakes in front and drums in the rear (or disc on all 4 corners) - not the other way around...

Yes 34" is the standard frame width on most medium trucks.

Yes my brakes are goofy with the discs on the back, they work fine for me but I'm not towing anything. I did my conversion on a small budget (3k) after finding the dana 80 with the ratio and bolt circle that I needed I was determined to make the brakes that came with it work.


2) Your Dana 80 has a 3.31:1 gear ratio and you're achieving 62 mph in 6th gear from a Fuller fs5306 6 speed non o/d trans @ 1800 rpm, with stock 9r22.5 Michelin tires and wheels. Does one really need the 4 speed Spicer 6041 aux trans with 15% overdrive? I allow you may want the under-drive ratios...

Your right I don't need the Spicer but I already had it in the truck.
Remember the truck is a big toy and shifting two sticks can be fun.

Seems like you're at optimum rpm for 62 mph, especially since OD in the aux box only drops your engine speed by 500 revs. 3rd in the aux trans is 3.31, or direct drive (same as the rear end ratio you have), and 4th is 2.86 for a .86 OD.

3) You stated the best donor for the 53-56 would be a late 90's Freightliner MT45 (step van/tool truck) because it has the Cummins engine with starter on the passenger side (if the starter is on the driver's side it will hit your steering box), and a Dana 80 rear end with the 6 hole bud wheels. Do these trucks come with manual trans or a Allison automatic? What about using the donor's front axle, or disc brake setup, in a F600?

The track width is too wide to use the front axle from the donor , (at least on my 56) It might work on newer f600

4) Can the 6bt Cummins be fitted into a C600 without major surgery?

Thanks for your help and any input you can give me will be greatly appreciated.

John[/QUOTE]
I'll PM my phone number to better answer your questions.

 

Since the thread is back up here are pictures (some from past posts)

 

Did you ever do the upgrades to your brakes.


Any info toward this would be great.


I have a 1956 F600.


Thanks
Al


I have a post asking about this.

 

[QUOTE=Al's_F600;16423496]Did you ever do the upgrades to your brakes.


Any info toward this would be great./QUOTE]

I have not done any upgrades to the brakes. I am still using the stock 56 f600 brake system, the dana 80 with disc brakes is the only thing that isn't stock.

Since you intend to tow, I would check into using the disc brake system from a f 450. I have been told that the spindles can be adapted to work on our trucks. Unfortunately I don't have anymore information than that.

Please post any info on your brake conversion, it would help a lot of us big truck guys.

 

What we did. The truck is a 49 F7 & we found a box truck and I think' don't
know, but some GMC we bought front and rear axles all big disk's. The
front spindles are just about exactly like the Ford but king pins are like a
.130 smaller. So I bored the GM spindles to except Ford bushings. What
ever GM axle this is, the drag link is the same as the Ford. I had to
machine an adjustable drag link cause the GM has the "tie rod end" and
the Ford has the typical ball cup spring adjustable. Bought that duel master cylinder set up with pedal for a 48- 50 pretty slick bolt up to original.
The engine some kind of turbo power stroke? with a HD AOD. I don't
know or care about new stuff I'm a flathead guy. All I care about is I ended
up with the 337 low mile flathead with a 5sp Clark overdrive !

sam

 

Rustyrelic

I have 2 questions for you.

Do you know the production years for rear end you used? I see a few Dana 80’s 1994,1995,1996,1997 available, I believe they are all from MT45's with 3.31 ratios. I have not found a 1999 like you, can I use a different years?

Where is the check values located in the brake system so I can remove it/them?

Thank you
Al