The C50

[morpheusmac]

Hey all,

I've been searching around for some answers on a truck that I inherited.

The story:

My dad passed away and left me a 1974 Chevrolet C50 Dump that hasn't really been maintained since the late 80's I'd imagine.



I remember being a pre-teen and I was told that if I put in some work helping with sorting and cutting some of the scrap that my dad collected that I would get a portion of what the scrap value was. My dad was a pack rat and had squirreled away ton of used brass valves, old copper wiring and fittings as well as some lead, stainless and misc other scrap. So I toiled for several weeks taking valves apart, cutting away copper from old equipment and sorting out all of the stuff left behind. My dad bought the old Chevrolet C50 dump from his work for $500 or so and we loaded and took scrap down to a local recycler and made something like $1800 in scrap from the proceeds, it paid for the truck and gave me a couple hundred bucks for my efforts.

Fast forward a few years in the mid ninety's and we were using the old beast modified with 4x8 plywood sides with the 8' sides used on the tall end to load dozens of christmas trees for recycling for the local boy scouts.

A couple more years after that I was doing another scrap run from the back yard with the trusty C50, cleaning up after my dad's collection of old car parts and scrap metal after re-decking the truck with plywood and re-wiring some of the lighting.

Fast forward ten more years and I bought my parent's place. They had allowed it to overgrow with trees and debris so I started cleaning it all up, cutting down trees, branches, clearing sticker bushes, moving dirt, etc. I was using the C50 to load up all the debris and take it off to the local yard waste center. As I started the cleanup at the house, my dad passed and everything was put on hold.



After a few months, it was time to get back to work. As it happens the truck was becoming less and less reliable over time naturally as it was abused and neglected. I decided I would change the oil on the truck, it was black and old, and the filter was rusty and illegible as to what brand it even was, I doubt the oil had been changed in 10 years at least. It had developed an issue with the steering where the truck would only turn slightly in one direction , but very far in another direction, I lived with it because I wasn't sure what the issue was.

I went back and forth several times debating on whether or not I want to put any effort into the truck at all, it's rusty, the wiring is hacked up, its old and nearly everything on it is a mess. But the memories I had of the truck that I shared with my dad as well as the utilitarian aspects of the truck were pretty cool, so I decided I would keep it and get it back to work.

The truck had now begun leaking brake fluid and transmission fluid, so whenever you needed to use the truck, you had to fill up both. I finally got scared enough to start doing some internet research on where to find parts for the truck and found this site and a few others in order to get the truck road worthy again. While trying to source parts I replaced the bed with 3/4" plywood.

The master cylinder was leaking down the firewall in the front and the right front wheel cylinder was leaking as well, I was able to source some replacement parts for those and get that portion repaired, but finding information on these trucks online is rough!




Cliff's notes:

Guy inherits big truck, guy wants to make the truck decent to drive and use again

So I am left right now with two big issues on the truck, first the steering. It is bad and borderline unsafe, the truck has power steering and while the pump and cylinder work, if the truck is unloaded, it has difficulty turning right. I get maybe one turn of the wheel to the right and two or three to the left until the limit of the steering is reached. When the truck has a good load on it, the steering issue usually goes away, so I am assuming that the steering box itself on the driver's side frame rail fried a bearing or something else loose in it that is causing the unloaded steering issue and I want to get that fixed. I've done some research here and I am looking for a SAGINAW 5690653 power steering box...any idea where I can find one used? Does this group have a parts guy or source that is decent?



Second the transmission is leaking. The truck has I believe a 350 chevy motor backed by an Allison 4 speed transmission. The leak appears to be the output shaft seal from what I see on the drip marks under the truck. I'd like to get this sealed up, but I'm not sure where to find that seal at or what the part number is for it, or how much of a PITA it is to fix?

Any help with the above and the plethora of other tiny questions I will probably pose about the truck here in the near future is appreciated.

Thanks,
Tom

[mrolds88]

Tom, first thanks for saving your dads truck. As far as your issues, the transmission should be an AT545. There should be a tag on the side. The steering should be replaced. GM should have used the same box for many years. If things hold true for the big trucks like they do for the pickups then the only difference would be the fittings would have switched to metric in the 80's. after rereading your post, yours has the type with the steering cylinder. I think, but not sure that the boxes between the power and non power steering gear may be the same. If it is it should be an easy fix.

[morpheusmac]

I feel like I have to save it, it is a great work truck, a bit rusty and somewhat of a mess, but it seems like everything on it is relatively easy to work on so far and relatively cheap! I picked up a new master cylinder for $60 and the wheel cylinder was $13.

Looking at the power steering box vs the manual box I think they are a bit different. Someone had a manual box for sale locally and it looks like it doesn't have provisions for the power steering lines like mine does. One of those popped about a year ago and I had a local hydraulics shop whip one up for pretty cheap. I'd love to find a used box for a reasonable price, looks like they are around $700 rebuilt through NAPA. Or maybe a rebuild kit? This is what the box looks like:



Oh hey, anyone know where I could find a throttle pedal for the truck? The whole time we've had it it has never had one!

[mrolds88]

OK. Wasn't sure that the box was tied into the hydraulic system. I would do a search for medium/ heavy duty salvage yards in your area. Then hit the phone.

[Deerelindel]

Originally Posted by morpheusmac

Oh hey, anyone know where I could find a throttle pedal for the truck? The whole time we've had it it has never had one!

Most of these truck parts are 67-72 truck parts as well, so for your gas pedal check there or i might have and extra.

[franken]

The gas pedal is most likely the same as most any 70s GM car or truck. Any repro place will have one, as well as the red help section at the parts store. People buy repro parts when the stuff is available locally.
PS box has hoses, and a manual box doesn't. You may get lucky and a manual box may fit, but a PS box is most likely at the local parts store, as are most of what you need. A box is ~$150 so it hurts a bit but steering is nice.
~750 in parts should get the old monster happy if you change _all_ fluids.

[morpheusmac]

Cool, thanks for the tip on the throttle pedal I'll take a look and see what I can find.

Is there anyone on this forum that is local to the Pacific Northwest? Anytime I call the local parts and salvage places, they tend to give me the run around on finding parts for the truck. I was hoping someone knew of a somewhat local place that has some old trucks or parts floating around?

[morpheusmac]

I picked up a repair manual for the truck for $5 on ebay, hopefully it'll be worth the $5!

[MjrBummer]

Hey morpheusmac,

What do you have for wheels on that thing? Are those still the 20" split rims?

[morpheusmac]

Yeah, I believe they are split rims, definitely 20." What are the options for those?

[1976gmc20]

Originally Posted by morpheusmac

Yeah, I believe they are split rims, definitely 20." What are the options for those?

I think you pretty much have to change tires yourself as no shop will touch them anymore because of the "danger" but I used to change them all the time on my truck with never any problems - you just have to know what you are doing. I don't know about finding 20" tires, though ...

Otherwise, you need newer wheels which apparently gets expensive fast.

You have to decide if you are willing to put a couple grand into wheels along with everything else.

[MjrBummer]

Originally Posted by morpheusmac

Yeah, I believe they are split rims, definitely 20." What are the options for those?

This is about our only choice right now for new wheels. I got a quote over the winter of about $245 a piece. Six of them and you're looking at about $1,500 give or take. I hear 9R22.5 are about the same size as the 8.25x20's.
http://www.wheelsnowinc.com/catalog/...em.php?id=1118

[1976gmc20]

If anyone wants information on how to safely change the old wheels, let me know and I will write something up.

[MjrBummer]

Originally Posted by 1976gmc20

If anyone wants information on how to safely change the old wheels, let me know and I will write something up.

I have a buddy who worked for Goodyear here in town a few years back. He's changes a few. He said the same as I've heard from others, wrap a chain through the hand holes a few times before inflating. Just in case something does get exciting, the fun will be contained.

Bill

[1976gmc20]

Originally Posted by MjrBummer

I have a buddy who worked for Goodyear here in town a few years back. He's changes a few. He said the same as I've heard from others, wrap a chain through the hand holes a few times before inflating. Just in case something does get exciting, the fun will be contained.

Bill

Yeah, except it's better to make sure they are together correctly

A clip on air-connector is nice, too - just stand completely out of the way.

Basic rule is that the two pieces should be loose after they are put together. If one piece won't rattle around or rotate relatively freely then it is not all the way on. I never had one blow up on me.

It's somewhat like mounting a tubeless tire made out of steel.

[83GMCK2500]

Tom, if you're still looking for a possible steering rebuild, I'd contact: http://www.redheadsteeringgears.com/contact-us They're local and from what I've read they're very knowledgeable and do great work.

[morpheusmac]

Originally Posted by MjrBummer

This is about our only choice right now for new wheels. I got a quote over the winter of about $245 a piece. Six of them and you're looking at about $1,500 give or take. I hear 9R22.5 are about the same size as the 8.25x20's.
http://www.wheelsnowinc.com/catalog/...em.php?id=1118

I'm fairly certain $1500 is more than the truck is worth right now

Are there any take off wheels that fit from the newer style trucks?

[morpheusmac]

Originally Posted by 83GMCK2500

Tom, if you're still looking for a possible steering rebuild, I'd contact: http://www.redheadsteeringgears.com/contact-us They're local and from what I've read they're very knowledgeable and do great work.

I got a hold of them a couple weeks back for a quote, they haven't gotten back to me after I sent them a couple images of the box. They are close enough to drive over to, but I was a bit frustrated about not being able to get a quote.

[jumpsoffrock]

Originally Posted by morpheusmac

I'm fairly certain $1500 is more than the truck is worth right now

Are there any take off wheels that fit from the newer style trucks?

Yes, there are random "bread truck" and delivery truck wheels that have the same hub diameter--the key unique factor to our wheels--but they are only in 19.5" rim sizes. There are no such thing as truly high-profile 19.5" tires out there, so you'll lose an incredible amount of top speed.

Aesthetically, they will look funnier than a jackelope.

These 19.5" wheels are also a bit of an anomaly and can be hard to find as well, but not too bad.





Have my wheels proven to be worth it? Hell no. (My truck is STILL sidelined with brake issues. First they dragged/froze; now one of the brand new seals appears to have failed and leaked oil all over brand new--discontinued--brake shoes.)

Would I do it again? Don't make me answer that.


Should you? Give it some really good thought before hand.

[morpheusmac]

Well crap, I'd hate to loose any more mph, its already made to do 55 with the gearing I have....What about the 80's style medium duty trucks? Or did GM just continue to use the split rims?

[rdauphinais]

Whaere did you get your parts from? Sorry if i missed that.

[jumpsoffrock]

Originally Posted by morpheusmac

Well crap, I'd hate to loose any more mph, its already made to do 55 with the gearing I have....What about the 80's style medium duty trucks? Or did GM just continue to use the split rims?

It appears that the split rims were used through the 70's, maybe even early 80's, but when they stopped, they also changed hub sizes.



There is no easy way out of this mess.

[morpheusmac]

Originally Posted by rdauphinais

Whaere did you get your parts from? Sorry if i missed that.

I get parts from Ebay or from Amazon depending on price and availability, figuring out what fits has been a pain, basically just looking for a part number and comparing it to what I have on the truck.

[morpheusmac]

Originally Posted by jumpsoffrock

It appears that the split rims were used through the 70's, maybe even early 80's, but when they stopped, they also changed hub sizes.



There is no easy way out of this mess.

Well ain't that a *****...no-one shares the lug pattern and offset on the truck?

[1976gmc20]

Are there no 20" truck tires (and tubes) available these days ???