The Stovebolt Site Forums The Parking Lot Big Bolts Need help identifying an Eaton rear end

I have a 1969 T50 chassis under a firetruck that has an Eaton single speed rear end. GVW rating is 19,500. I am trying to ID the rear end for model number or any other information that would help with replacing the diff.

The glove box sticker lists the rear axle as "Option H21BA, H170, 6.17 ratio".

Crawling under the truck I found the following:
Bottom front of the pumpkin "3826111GM", (likely a casting number) with "D2" below and "276" at 90 degrees to the long number.
Top left side of pumpkin, stamped in "JV1167C2"
Top of pumpkin flange, between 2 bolts, "X"
13 Bolts

On the outboard axle shaft face, "T75" and "S13", each repeated twice, 90 degrees apart. Nothing along the edge of the axle flange.

Anyone know what any of these mean?

Thanks in advance.

My question has been answered, I have a GM H170 axle, thanks to everyone.
sweepleader is online now Report Post [color:#33FF33][/color]

My parts books stop at 1967, but I think you have a 15,000 pound Chevrolet rear, not Eaton.

Does it have hydraulic brakes?

3826111 looks like a Chevrolet casting number.

Post a picture of the rear...

Mike B

Yes to the hydraulic brakes, HD spring option according to the build sticker, the brakes are different (larger) than the standard version. I never did find wheel cylinder listings that were correct. I had to use generic rebuild kits, they still leak a little. The brakes are 15 x 6, I have worked on them a couple of times.

I will try to get a picture that is clear.

Here are some shots of the unit in question, I only have bad ones of the rear cover (as if the shots of the front are good, lol) but at least it can be seen that it unbolts. I rechecked the chassis service manual that I have which I think is where I got the idea that it was an Eaton. The bigger truck rears are listed as Eaton, the mid size are not named, just generic instructions for service. No pictures in the book that can be identified as any make so Chev must have used whatever was available.

I searched some for the Rockwell H170 but none of the pictures I found look like this pumpkin. They all seem to be much smoother, without all the ribbing. They might have been pictures of other models, in some cases there were many models listed with the same picture.

Hy sweepleader, your link to the pictures says we don't have permission to view them?

I found the directions to picture posting, that should be better.

Hy sweepleader, thanks for correcting the pictures, it looks like Mike B is correct you have the corporation (GM) single speed 15,000 - 16,000 lb. differential, not an Eaton at all, hope that helps.

Someone will correct me if I'm wrong but I believe the G.M. axles of this vintage have axle shafts that spline into the hub with a metal cover over the end the hub where Eaton axle will have a flat flange that attaches to hub with studs & nuts.

Hmmm, these axles are one piece with the drive flange, 8 studs in the hub with cone washers and nuts. No splines at the hub end, no cover other than the axle itself. ( I wish I had counted the splines when I had the axles out!)

What is your wheel bolt pattern? Why are you concerned with your axle? Just about parts or a higher ratio? You might be able to find a more modern axle with your wheel bolt pattern, or a two speed diff? If that is what you are after.

Ed

I have positively identified the axle as a 17,000 lb GM unit.

The truck has cast wheels and demountable rims, (Detroit wheels?), so I am guessing that changing the entire assembly is cost prohibitive. GM did make a 2 speed version of this but the gears that appear to be available are even lower, no help. The only concern I have is too many rpm's on the highway, just like most other old truck owners I guess. I would like to drive it farther afield, many of my "local" events are a hundred miles away. The truck has less than 6000 miles at this point so I don't think I will ever wear it out. At least now I know what I have in case I run across something by chance. I will spend some time cleaning the tag on the transmission, it was painted over, and determine what model of Clark it is, (I can read "Clark", just not the model). Maybe an over drive will fall my way.

Hy sweepleader, I'm glad you identified your rear axle. The picture you linked to says private, we can't view it.

The wheels you have on your cast spokes are called "Dayton Wheels". The spokes can accept both 20" tube type split rims or the 22.5" tubeless one piece rims.

The 6.17: 1 rear gears were the fastest gears available and you should be able to run about 60-65 mph all day long. My 1957 Fire Engine has 6.14 gears and that's what I run on the interstate. It takes about 1 mile to get there but once there it runs fine. My truck had 11K miles when I got it and it now has over 41k. Don't be afraid to bump the governor once in a while, the engines are made to run wide open all day long.

Get the truck running and drive it for a while before your tear it apart to make it go faster, you might be happy with the speeds you get as it is...

Mike B

Well, I think the picture is fixed, I can see it, I could see it before. Anyway, hopefully its OK.

As far as the engine speed is concerned, I know the SB Chev will rev like mad but I also know that 4000 rpm is too fast for me for more than a short period. I drove the truck 500 miles on the first trip home when I bought it. That is a whole other story but I did get a bunch of miles right off. Given the results of this search and other considerations regarding mods to lower the engine speeds, I will indeed have to get used to the 6.17 gears. I have owned it for not quite 2 years and it is a gas to drive. Huge compared to my other vehicles, small compared to other fire trucks in our local club.

My 62 K10 has 3.90 gears and 31" tires, it runs 60 at about 1800. Quite a bit different. The torque peak is right there and its really fun to pass with, nothing it won't get around before the next no passing zone. The fire truck will not be passing anyone who isn't in a gas station.

Sweepleader,

Since you live in Minn, I have a GMC 620 fire truck that had 6.5 gears. A gentleman in Duluth, who is an old time axle and trans. rebuilder fixed me up with a rebuilt two speed, 4.33 diff. I took my old single speed out and installed the two speed over a weekend, so it is not much work. Lee Atchison knows a lot. The MN of your axle might be on a tag on the glovebox door, that would be helpful.

When your tires wear out, if ever, Dayton wheels come tubeless in 22.5 size, which are interchangeable with your 20's, so you might keep an eye out if you wish.

If you would like his contact info, PM me.

Ed

Your pic works. Nice looking truck. Whereabouts in our fair state are you located?

Thanks, the picture is from a year ago, I have found suction hoses for the rack on the near side and a ladder for the far side. All the portable equipment was missing when I bought the truck. Most everything else was there.

I am located a couple miles west of Wayzata, how about you?

What engine do you have? I had two different 1970 Chevrolet Tilt Cabs and one had the GMC 478 V6 and the other had the 427 V8...both were 5+2 and both had a max speed of about 53 mph.

Do you still have the John Bean booster reel hose nozzle's? (click on IMG link if the picture of the nozzle doesn't appear)

Does your truck have two pumps (High Pressure Fog and the mid-shaft Volume/Pressure Main Pump)?

Are there two axes on the back panel?

Here's a picture of my 1957 Chevrolet/John Bean.

Mike B

Looks like the same Bean body except that mine has a cabinet across just behind the cab, sort of like a cross lay but no hose or connections in it.

Mine does have two pumps and I do have the nozzles. Both high pressure hoses were complete on the reels when I got the truck with the nozzles in place. The hoses had been frozen and were broken open at the bottom of most of the turns on the reels. I cut out many bad sections and salvaged about 50 feet out of 400 total. Looking for more hose but I have enough to play with. My reel covers are somewhat different than yours. The retract motors are inside and the lids are squared off. They open with and awkward lifting/sliding motion.

There are two axes on the back, along with a nozzle bracket on the left side and an Indian pump can on the right. The nozzle and pump can are not on in the pics below.

My tail lights are about 8" in diameter and there is one same size back up light in the middle.

Mine is the first year of the 350, only rated at 200 hp but it can almost get out of its own way. 5spd Clark, no OD, and single speed rear end.

Here's a pic that shows the back and one of the reels.

500 gpm with a 500 gallon tank?

You have the newer style reel covers, not sure when they were introduced.

My quick fill is on the rear, but other than small things the body is the same as yours.

The front pass through cabinet was a COE cab thing...made the body to long on a conventional cab truck.

The Deck Gun is a neat feature...takes LOTS of water to run that...must have been a city truck that had hydrants.

My truck came from a town of about 2000 people and was the only truck they had for it's first 13 years of service...it did it all! They but 11k miles on it over it's 38 years of service.

You could look for a newer rear with better gears and just swap it all, but finding one with hydraulic brakes might be hard. Just keep driving it and over time you'll come to appreciate the slower speeds.

Mike B

Sweep, I'm down east of Mankato.

Yes, 500 gallon and 500 gpm. I measured the tank just for fun and it calculates out to 625 gallons, sort of struck me as odd. I guess the fire service was/is stuck on certain sizes of tanks. You have a Waterous pump too? They were made in St Paul, still are, about 25 miles away from me.

Funny about the cabinet, the chassis was lengthened 9 inches to accommodate it!

The deck gun is an addition, a friend of mine got it for me, it is from the Minneapolis FD, siting on a box I built. We use it for squirting at gatherings, the public really likes water displays. We have trouble with the tree huggers, they think we are wasting water even though we are squirting into the same pond/river we are pumping out of, go figure. The nozzle on it is only 150 gpm max and I turn it down because the public can't tell the difference between 100 gpm and 1000. With a smooth bore nozzle I suppose it might take 1500 gpm. Minneapolis has lots of water, several other guys around here have them.

My truck came from a small rural town too, in western ND. It was also their first truck and was in service to at least 2006, that is when the pump was last certified. Quite similar to your truck's history. I tried but could not get much out of the FD there, no one wanted to talk about it. I guess they were glad to get rid of it. Not many miles either, I added over 10% driving it home.

I see you also have a NAPCO truck, I have always lusted over them. Somewhere I have a factory sales kit (for 1957 I think), when they first were offered by Chevrolet as a dealer option. It has original 8x10 photos of a 3/4T Suburban demo and lots of "this is the best thing since sliced bread!!". I got it from a customer when I owned a small garage! NAPCO is located about 10 miles away from me in Hopkins, Mn, the original building is going to be torn down this summer to make way for a light rail commuter train. My 62 is one of the first factory 4x4s that Chev offered, people ask a lot if it is a NAPCO, its the reason the guy gave me the sales kit.

The slower speeds are the reason for the amber light on the back of my truck. Driving it home across ND in a 70 zone, with traffic moving at 80, it was plenty scary holding a steady 50 and watching them pass without slowing. That is really the only reason I want to speed up the truck, events around here tend to be 100 freeway miles away.

I will likely just leave it the way it is unless I happen across an easy solution, there are enough other projects around that I don't need to add a tough one.

Hi Rich, love your truck. You could bring it to a meeting of the Minnesota Fire Engine Club (https://www.sites.google.com/site/mnfeclub/home) some time. We will be in Northfield Saturday of Memorial Weekend with an all afternoon into the dark pumping display. We only have a couple of trucks older than mine but you might have a good time.

I'll bet it has deep gears too and you don't drive it far very often, the Northfield raid will be the farthest I will travel this summer with the truck.

Hope to see you sometime, keep that '47 polished! (I hope you have kept the side boards!)

Sounds like an Eaton

When you measured the tank did you take into consideration that the tank doesn't go all the way to the side walls of the body?


Both of my pumps are John Bean pumps...



I sold that truck to The Museum of Off Road Adventure in Michigan about a year ago. I had WAY to many irons in the fire and it got a good home.

Mike B

I do still have the grain sides for it. We could have it ready to haul corn again in less than a day. Right now I have 12" sides on it.
You're right that it doesn't get driven too far usually. I took it to the Le Sueur show a couple times, but most years it doesn't get 100 miles put on it. I don't have a working speedometer right now, but I'm guessing around 50-55 mph is where it's comfortable at.

When you measured the tank did you take into consideration that the tank doesn't go all the way to the side walls of the body?

Yes, I measured the tank itself. I did not include the sump which is about an 18" cube. My tank has a step in it that I did account for.

I never heard of a John Bean volume pump, that is interesting. Have you seen the John Bean FB site? Lots of information there. Also SPAAMFAA (http://www.spaamfaa.org/) has a great page on John Bean. I guess you have to join that organization to get at the John Bean page. They have a listing of all the Bean trucks delivered up to about 1966, at least I think it is all. My truck is not there, it is too new. The list shows dates and original department.

Here's what I have...you might have to click on the link for the second picture

Mike B

I checked my manual, they use the same pictures and the dimensions are identical other than the weight. Your specification page is very nearly identical to mine. I am gonna guess that you have a Waterous pump too. I believe Waterous is cast into the front of the pump.

John Bean started as an agricultural equipment maker and the high pressure pump was one of their specialties, fire trucks were a side line. They built fire trucks to sell high pressure systems. I am pretty sure they never made their own volume pumps. I don't have any proof of that and others would know more than me about the issue.

Do you have the full Bean Manual?

I've never seen "Waterous" written, stamped or cast on anything on my truck, but that doesn't mean you're not right.

Yes, I have the manual. No I've never been on the FB site and I'm not a member of SPAAMFAA .

I think it's time we start a new thread in the Firebolt Section to talk about John Bean stuff, we have strayed way off topic.

Mike B