Rear differential suggestions

[Driver_WT]

Originally Posted by Missyblue

Thanks for the advice. Yeah my husband thinks I'm nuts and should do it right as a frame off but then I know I'll never drive it so that's why I'm here pestering you guys for advice. I don't have lots of money and so trying to do it the "right" way for us and get it running affordably. But also doing my research because if I can do something like get a Ford rear end with disc brakes for less than updating my brakes later that might be the way to go so trying to be smart about some of those decisions. Im working on my priority list and will keep all your advice for options. But at this point getting on the road and safety are number 1 and then upgrades for comfort are later like you say.

Good luck with your build. Sounds like you are getting to a plan.

[Missyblue]

Thanks I am getting a good start thanks to all the help. I have alot to learn so trying to process 1 thing at a time. Dad's gonna teach me how to change my oil this week haha. Starting with the basics. Just figured out what bolts to buy to get our front end put together...then Got engine and tranny decided 350 and 700r4 now working on differential and brakes and then on to other things so I'll be pestering you guys some more soon 😊

I would love to see photos of your trucks for inspiration if you have any handy otherwise I'll just stalk the threads on here for ideas

[_Ogre]

Originally Posted by nail pounder

Nice looking truck! I'd say drop a motor and overdrive trans(700r4) in it, leave the original rear end, fix the existing brakes and drive it. Then tackle your list as money allows. They are more motivating to work on if you can take it out for a drive once in a while.

best advice you'll get here

Originally Posted by Missyblue

I don't have lots of money and so trying to do it the "right" way for us and get it running affordably.

with this clarification, the nail pounder method is the route you should take

even then you'll have to fabricate and weld in new motor mounts and trans x-member. not expensive if you take some square tube and just do it. expensive if you buy kits.
shorten the driveline. adapt the stock shifter to 700r4. rebuild all brakes, mc and wheel cylinders. probably replace the front axle kingpins and tie rod ends

if you do disc brakes on one end only it should be the front end. new rearend with disc brakes means all new brake lines, shortened drive shaft and adapting a master cylinder for drum/disc
these trucks have many millions of miles on them in stock configuration and there are plenty of stock trucks still running around in stock configuration

lots of cool projects going on in this forum, many of them last for years and years
i know that well enough: my 58 truk took 8 yrs

[dsraven]

if money is tight and you just wanna get it running and ad stuff along the way, think about checking the front end to make sure it is good to drive safely. the family will likely be in there at some point so don't take chances on the safety stuff. do the kingpins and tie rods if required. check/replace the stock brakes as required. drop the engine in (ya, I know, sounds easy but no mounts yet) and get a shifter figured out for the automatic, maybe need to get a driveshaft made up and some exhaust. then, if the rest is already good, like the lights, wipers, tires etc, you could be driving it. std steering and brakes. as you upgrade things think of what you want to end up with. if you want disc brakes up front there is a kit that will work on the straight axle and upgrade to 5 lug chevy wheels but if you also plan on doing the rear end and are thinking of the ford 8.8, maybe there is also a kit that swaps out to a ford pattern,(think of this if you need to buy wheels for the 6 lug truck to run stock, no use spending cash that you will just set aside as used parts later). otherwise redrilling the ford axles and brake rotors/drums is something you can do yourself too. the ford pattern is also 5 so just drill the axles for the chevy pattern between the ford pattern and replace the studs with the same size as what the front will have. if you decide to do that I suggest to do the front brake change and the rear axle change all at the same time. possibly incorporate a power brake unit at the same time to simplify things. power brake master cylinders are usually a different bore size to compensate for the added pedal effort from no booster. also, a disc front and drum rear is a different master cylinder than a disc front disc rear. a drum set up may also require some residual valves if not already in the master cylinder ports. if doing the 8.8 axle you could get rear discs as well. explorers have that option as well as posi and larger axles. check

http://www.therangerstation.com/tech...8_8-axle.shtml

for more info on that.the center section is offset on an exploerer but there is also a mustang 8.8 unit available from the mid 90's that is centered and possibly the correct width. when you get the rear axle also grab the park brake cables, the link that connects the cables, the master cylinder and proportioning valve, the rear brake hose and a section of the steel line in front of that so you have the correct fitting, the stabilizer bar and links and the rear part of the driveshaft (the ford flange is a flat unit and the drive shaft shop will need that rear flange from the actual shaft in order to build you a new shaft or adapt your old shaft). the ford diff will need to have the brackets cut off and repositioned but those new spring pads are available at trailer or rv shops for cheap.that will give you power disc brakes on all 4 corners. if looking to upgrade to power steering later there are kits available for the solid axle as well. maybe th best one is the gm 400 box which will mount in the stock location, allow full turning radius without having the tires rub on the box like some and not give bump steer like some conversions. there is a power assist unit available as well but, personally, I would steer away from those just because I have had issues with them leaking etc in the past. the 400 box is also available on some older toyotas. you could google it for more info on that. this will give you most of the stuff you want, minus IFS, and still allow you to drive it daily, except for the time it takes to do the mods, and you can achieve it all as the budget permits.
lots of guys are still driving around on the solid axle. lots have done the disc upgrade. those kits aren't for sale because they look good in a magazine ad.
good luck and post up some pics as you go.
as a side note. personally, one of the first mods I would consider doing is to get the fuel tank out of the cab. fuel vapors are carcinogenic and you are driving around with a tank of gas strapped to the back of your seat.plus it gives a little more room behind the cab for "stuff". power steering and brakes will make it a lot more fun to drive. a 700r4 trans will give you overdrive so it isn't screaming at highway speeds and also has a lower first gear to get things rolling out of the hole. doing it the slow way as you drive may take awhile but you also get to drive it and will appreciate each upgrade as you can afford it. a fuel injected engine will also make it more fuel efficient and easier starting, but would also require some wiring and a different type of fuel pump. if you get a donor vehicle for the driveline try to keep as many usable parts as possible, steering column may also be required at some point down the road, depending on how your build goes.

[Missyblue]

Thanks this is exactly the knowledge I'm needing
So long story short my truck was a father son project. They gutted her about 10 years ago his friend painted her and that was the last of it. So I know I am missing little motors and accessories. Im still trying to dig and see what i have and dont have.
For ogre or anyone who can help. He bought a mount for a v8 engine I'll try and get it out for pictures and info so I'm hoping it will work as far as transmission my dad can do some welding woukd you be suggesting like 1" square iron? And do you have any insights on or suggestions on how to do it. I havent started looking that up yet. I can try research on my own too. My dad is very crafty but even a photo in a build of someone else's would be helpful.

Adding in dsraven thank you for the insight. 1 mechanic I talked to didn't tell me all the things I needed for the differential so if I go that route thank you so much for the parts list to include. I'll try to address some of your points....

I currently have a standard column and no shifter. We are thinking it would be nice to do an automatic column and not a floor shifter for eas of having my daughtrer in the middle so I'm needing to resesrch columns that hopefully will also adapt to power steering someday if you have any suggestions that way. I heard that the tilt columns can sometimes be a problem?

And your comment is precisely where my head is. I hate to spend 300 getting my differential and drums running just to want disk brakes if I can potentially get a rear end with disk brakes for around that cost. So trying to consider options and also needing to look around here and see what options i might have. I need to understand the master cylinder better and I need to crawl under my truck I'm not sure I even have one to start with. You both brought up that it would need different things/setup for the master depending on what option I chose. I apologize I haven't got to researching that yet so I have no understanding of what I need there yet. If I have to buy one and wanted to stay with drum for now is there one that would be upgradeable to disk later? I know for sure I don't think my husband will let me leave the driveway without at least power front so I would be looking for at least a master that does power/drum and a kit for disk front. Although 1 mechanic suggested power master cylinder with my drum brakes? Would that be a viable starting place?

I'll start researching the power 400 as well for the future day of power steering!

And yes I have looked into some tanks and plan to move that out of the cab and appreciate your advising me on the safety concern.

I know I didn't get to all my questions regarding all the info you gave but this is a start.
Thank you again for sharing your knowledge. I am so excited to learn about this truck and keep making a plan. I found the original in a photo here she is for fun. I was about 2 I guess. This is the inspiration to get my dad and I a truck to share. I actually wanted a more patina and old looking truck but the ones I was finding were too rusty or too expensive and the one I got didn't need so many repairs so we will have a fancier version of our old girl I guess

[1project2many]

You've probably already realized there are a *lot* of excellent builds and very talented people on this forum that are willing to help out. It looks like your questions have changed from advice about the rear axle ratio to advice about a direction to go with your project? I'm usually in the minority here because I prefer a more practical and less expensive approach to building a good truck but I'll share my perspective.

Truck projects can take much longer than expected. Mine was already on the road and running when I started the body work. Three years passed before it drove out of the shop. For cost and simplicity I left mine mostly stock. It still has drum brakes, still has the stock rear axle and transmission, no air conditioning, and the original manual steering as well. I even left the same brake shoes and shock absorbers on the truck that were there when I bought it. Most of the folks on this forum wouldn't keep their truck at this basic level but I've been using mine since '98 and enjoying it the whole time. And despite what I seem to see on the forum most of the parts on the truck are capable of surviving well in daily use.

With your truck already painted it would seem like any changes or upgrades should be planned so bodywork and paint isn't touched. I don't disagree with the safety concerns over the original single chamber brake system. The master cylinder is underneath the floor of the truck and there are kits available to put a modern dual master cylinder with brake booster under the floor. The original brakes do require some effort to use and if you mostly drive a vehicle with power brakes the manual system will seem like it's fighting you as your driving day gets longer. If you replace the drums with discs you're probably heading for a replacement master anyway to make the brake balance work out. I'm happy with the drums on mine but I am going to add a '60s vintage brake booster in order to get power assist.
Edit: The early Chevy vans also used beam style axles. This disc brake swap seems well documented by someone with good experience: http://www.angelfire.com/wv/joyrde/v...scBrakes1.html


The factory steering parts were designed to work with skinny, stiff, bias ply tires. Switching to modern radials requires a lot more force applied through the components and you may find driving to be tougher than expected. My truck didn't seem tough to drive when I was in Montana where we had wide roads and little traffic. But back east people drive very agressively. Stop lights here are sometimes only a couple hundred feet apart and there are plenty of folks racing to be the first person to stop at the next light. Plus many of the roads here are in pretty rough shape. Driving with these folks is a bit more challenging. Since I'm not getting any younger so I have plans to improve the steering components and possibly to add power steering to the old solid axle. Like your truck, the body work on mine is done so any changes I make will not involve redoing the body.

An automatic transmission is a great idea. And I agree that keeping a shifter out of the center of the truck makes riding with a child in the center much easier. '55-'59 GMC and Chevy trucks came with automatic transmissions so there are column shifters that bolted directly to the original column. They are likely to be tough to find and expensive but I wonder if it would be relatively easy for a creative person to build something similar or to modify a 3 speed shifter for the original column. Most folks end up adapting a later column instead of working with the original part. Since the original box and column don't easily separate the original column and the steering shaft will need to be cut and and modified to connect with the later column. Many folks seem to buy a column from a RWD car but I wonder if a later FWD column might be a good choice. The FWD columns are shorter which might allow the original column to be cut inside the cab of the truck. The FWD car columns also use a cable between the transmission and column which might be easier to adapt to the automatic than building linkage.

My real lament is that there's no room in the cab of the truck. For years it was only my wife and myself and we could bring a small cooler and a bag when we went on long trips. Once my son came around it was much tougher. And with two kids there's no way everyone can go out for a drive. If you are looking at making any changes inside the cab I'd recommend trying to incorporate more storage space.

Good luck!

[roger55]

Missyblue,
If you haven't seen my build thread, I think you may enjoy seeing it and it may give you some ideas. The link is in my signature. It's very, very detailed and has many large sized photos.

My take on the rear end is that disc brakes aren't necessary. You want them on the front where about 80% of braking force comes from. A front disc, rear drum power brake system is by far the most popular thing done. I went with the CPP 6-lug disc kit for the front with their power master that mounts on the firewall. I love it. The brakes are perfect in the truck. The kits have a few quirks with installation but the end result was terrific. Details are in my build thread.
I also detail the mods I made to use that drum brake '65 GMC Dana 44 rear. The 3.54 posi and 700R4 combo couldn't be better.

Truck as purchased:



After my 2-year restomod:

[dsraven]

just a side note, but if you plan to do anything with the brake master cylinder do your homework first if using a donor master cylinder. a disc brake master cylinder is different than a drum brake master cylinder and a disc front drum rear is another difference. the drum brake portion of the master possibly has a residual valve built into the outlet port to keep a bit of pressure in the line. this keeps about 2 lbs pressure I think, because there are springs to retract the brake shoes with drum brakes so 2 lbs keeps dirt and water from entering. disc brakes simply rely on the o ring in the caliper, which rolls slightly with the piston movement, to want to roll back and retract the piston as it comes. a disc brake system doesn't usually have residual valves. you can interchange a bit probably but an inline residual valve may then be required in some instances. some guys will remove the residual valve from the master and use inline ones to control the amount of pressure kept in the line. the other thing to look into is the possible requirement to have residual valves in the lines when the master in almost at the same level as the brake calipers. this is something that some guys have had issues with. too much residual in the line can keep the brakes lightly applied and they can get hot. if doing a power brake unit you may want to look into the hydroboost units. check ogre's or kim57's threads, they have both installed one. in different configurations they take less room and give a good power boost. like said, depending on your driving style and needs, city driving is different than country driving, mostly, so your needs may be different than some guys posting. radial tires, stopping distances, gravel or paved roads, loads carried, sizes of parking stalls these days, etc.
if doing a steering column from a donor I personally would not use a front wheel drive unit because they require more support in the dash area than one that goes through the firewall and is supported at the dash like a rear wheel drive vehicle uses which is mounted on the dash and also at the floor. if in an accident a front wheel drive column could come apart and pivot the lower section up to contact the abdominal area.

[_Ogre]

as for motor/trans mounts they are simple to fabricate with the most basic tools and scrap steel
this is similar to what i built in truk 1.0 for motor mounts and a trans x-member
i used some 10 gauge flat plate and 1.5'' square tubing, cut everything with a $12 harbor fright grinder and cutting wheels

all rubber parts are 68 chevy truck, they are easy to find and you need to give a year/make at the parts store

[dsraven]

here is a link for something to use for a stock column where it is cut off under the floor, if you go that route. you would still need to have a shifter for that auto trans. a shifter from an envoy (cable operated floor style and would have capability for a floor mounted park brake as well) may work if you have buckets but then it is a 2 seater only

https://www.ecklerstrucks.com/chevy-...1947-1959.html

then something like this to connect the dots to the steering box.

https://www.ecklerstrucks.com/chevy-...1947-1959.html

some guys are using a steering column from an astro van from '80's. they are smaller than some of the newer vehicles and have a column shifter.

after seeing an engine mount and trans cross member you can see that it wouldn't be hard to make yourself if you have some scrap like that and a bit of time. I made mine from 1 1/2 square tubing and some flat bar I picked up at a scrap dealer. some of these simply bolt to the lower flange of the frame and some, for units with a little more HP, will bolt to the web section of the frame or connect the upper and lower flanges of the frame for better strength and less frame flexing. keep in mind that some one will need to run exhaust through the area. make the engine mounts first (remember to leave room for the solid axle to move up and down to it's full extent, if using the solid axle and possibly lowering the truck in the future, and also try to have the engine sort of sitting at the 3 degree down angle so the mounts will be welded in pretty close to the final angle. otherwise the rubber in the mounts will be constantly flexed and won't last long) and then have the engine and trans placed with the engine bolted in loosely and the trans sitting on a jack or blocks. keep the engine low and back but remember to leave room to mess around with the distributor cap or to remove the distributor. then the engine would need to have a downward slope of about 3 deg down in the rear. with the truck sitting normally on a level floor at ride height. install the trans mount and then fab a cross member that would support the engine and leave a little air space, like 1/8 or 1/4" under the mount between the cross member. this will compensate for the squish of the mount with the weight on it and also allow some fine tuning with shims to get the trans at the correct angle for you. slot the mounting holes for ease of assembly. after that find some exhaust manifolds that will fit and leave room for the steering box and shift linkage.

[57chevyman]

I have what you definitely dont want on my truck. i bought it this way, and since i only drive it around the neighborhood, i havent made changing the rear end gearing a priority,,
i have a SBC 350 from a 1977 truck. 3 speed saginaw tranny on the floor. rear is a 1975 GM rear with 4.11 gears.

between 0 - 40mph is alot of fun. 50mph is about the fastest i ever drive it if i make a short run on the highway. thats with the rpms around 2000. to avoid having the engine screaming all the way , i press the clutch all the way, so i can coast a bit.

i either need two or three more gears and the same rear, or new rear gears and same tranny. i kinda like the manual tranny, but ive also considered going to an automatic with overdrive

[roger55]

If you want a manual, go for a T56. Most of the used ones have a .50 6th gear. It would make your truck a blast to drive in town and highway and you can keep the 4.11.

[dsraven]

here is a pic of a cross member I fabbed up from 1 1/2" square tube and some flat bar. the trans mount sits in a plate welded to the front lower side of the square tube. the ends of the member sit in the lower flange of the frame.
hope it helps

[dsraven]

I should mention the frame is boxed so the member sits on a flat bar "rail" welded to the truck frame. task force truck

[Missyblue]

Thank you kindly for the photos and advice I have alot of great info to consider in making my plan. You have all been so helpful.