England Calling 1990 Oshkosh Chassis

[peterk]

Hi can anybody kindly assist We have a 1990 Oshkosh Chassis (puller) with a Cummins BT6 and Alison 4speep auto box with a Gulfstream Body. Chassis Number 4CDB4XE28L2101312 We are trying to understand the Braking system and what brake fluid we need to use. I believe your group has Oshkosh specialists, can you kindly put us in touch. I\'m a competent Engineer and I want to avoid expensive mistakes. The brakes are not brilliant and there does not appear to be a Brake Booster. I have found a small vacuum pump under the hood but it looks too small for any Brake boost.

Can we thank Todd Moning for his kind assistance.

By the way I lived in AZ for 6yrs and loved it.

We look forward to your comments and suggestions Best regards Peter

[wolfe10]

_peterk,

_{Welcome to the FMCA Forum.}

<sub>Oshkosh sold out to Freightliner.

Most of that vintage had hydraulic brakes. Many hydraulic over hydraulic. So the brakes themselves (i.e. in the master cylinder) is regular DOT III brake fluid. There were a number of different fluids used in the engine-driven hydraulic system including engine oil, ATF and hydraulic fluid. Suggest you confirm this with Freightliner.

I don't have an e-mail address for Freightliner Chassis which is in Gaffney, SC, but their phone number is: 800 385-4357. Contact them with your VIN.</sub>

[nitehawk]

Maybe I can help. Our coach is a 1989 Foretravel 36' diesel pusher with the Oshkosh chassis. It has leaf springs all around, with shocks. Our engine is a Detroit Diesel turbo-charged 8.2 Liter V8 with a four speed Allison transmission. Does this sound like your chassis (except for the engine?). The brakes are hydraulic, with an electric assist pump mounted under the floorboard on the side of the master cylinder. It uses standard brake fluid (DOT 3) . Our chassis number is V-817-2. Oshkosh sold the frame design to Freightliner back in the 1990's so find your chassis number and you might get lucky with them. Otherwise, send me a PM and I will try to answer any relevant questions and hopefully my answers would apply to your chassis also. Just saw Brett's post. Go for it!! Take what he says as gospel. I know!!

[obedb]

Bought a new gasser in 1988. The chassis was referred to as a John Deere, but quickly became a John Deere/Oshkosh when Oshkosh bought the chassis division. Ours was also four wheel disc brakes that were hydraulic. Suggest a brake fluid flush if one hasn't been done in awhile. Brake fluid is hygroscopic. When the water boils braking force is sometimes all but lost. There was a parking brake on ours between the drive shaft and the tranny that was spring applied and released by vacuum if memory serves. Maybe your transmission is stronger, but the parking pawl was removed in mine. Gotta be a lot of info out there because quite a few were built. Ours was powered by 460 ford with a Holley built (Ford) carburetor. What a noisy beast!

[dickandlois]

petek,

Welcome to the FMCA Forum!

Your chassis could be equipped with hydraulic over hydraulic as mentioned by Brett. Some chassis did have the electric assist.

The Vacuum pump you found is used to supply vacuum to the Heater / AC and defrost system to switch the air flow to the area or outlets you want it. The default position, should the vacuum system fail - is the defrost position.

This is a link to a Manual for a 1989 John Deere chassis. This manual is a very large PDF File about 950 pages. So it will take some time to download !

http://www.cdr-roc.com/89JD/89-JD-Chassis-manual.pdf

This is a link to a owners manual from Airstream on a Oshkosh Chassis that might prove help full. This manual is 172 pages long.

http://www.airstream.com/wp-content/uploads/archive/f645b72106e6e2a8.pdf

Rich.

[peterk]

You know Guy

NOW I know why I really miss being in the States, THANK YOU everybody I got more info in less than a day than I've been able to find in months. Fantastic, I will begin to digest the info you have all kindly sent through.

I will be replacing the Brake Fluid as I have run into this problem before on older vehicles. The problem here in the UK is narrower roads and shorter braking distances, we took it to South Wales on the first trip, and there were a few white knuckle moments.

I would like to try and track down more info on the Electric Assist. On this Gulfstream the Floor panel is fixed and about a 1inch clearance above, so I think we're going to modify the floor panel to gain good access to the Mastercylinder.

Does anybody know if there are New Seal Kits available for the Master Cylinder and wheel Callipers ?????

Happy Motoring to you all and thank you all so much for pitching in.

Best regards

Peter

[peterk]

In case its helpful

the Email address is:

fcccservice@daimler.com

I'll keep you all posted

Br Peter

[dickandlois]

Peter, you might try looking around the Federal Mogul and National Seal sites for the caliper seals. They might supply seals for the master cylinder and cover.

Rich.

[hermanmullins]

Peter,

It's been years since I overhauled a master cylinder or wheel cylinder, but if I remember correctly the seals had numbers on them. If you have them apart and there are numbers contact, as Rich said, Federal Mogul and or National Seal. If there are no numbers take as closes as possible measurement of the cups and bore size then contact the same folks.

Good luck and keep us up on your progress.

Herman

[wolfe10]

On most hydraulic over hydraulic brake systems, the electric assist is generally only an emergency backup. It works if the engine stops. So, turn on the key, engine off and you should hear it run.

[peterk]

Morning Guys

Well, the people at Freightliner in SC have been incredible, I got the info below in about 10 minutes.

Dear Customer,
The VIN number you provided is a MC chassis built in 1990.
The part number for the master and boost cylinder is GAF RW24255
The part number for the caliper assy in the front is TDA A3263E1019.
The part number for the rear brake calipers are DTW 60450395
The only repair kits I have is for the calipers. DTW 60050198. This is for
both front and rear.
The Freightliner dealer for international parts is Stoops Freightliner in
Lima OH. There number is 419-228-4334


Sincerely,
Glenn Hoops
FCCC Representative



[DTNA Call Center Email]
[Queue-FCCC_OTHER_EMAIL]
[Tracking Number-000330642]

fcccservice@daimler.com

12:19 PM (20 hours ago)

to me

I'm pretty impressed. We'll begin with renewing the Brake fluid. Thanks Herman, a good thought I'll check for numbers on the seals. Also thanks Brett, I don't think there's one fitted, I'm going to ask at Freightliner in case there's a later model Brake Booster (what we call in UK a Servo assist) which can fit. But first steps first we'll replace the fluid.

I have to tell you the Chassis is in like new condition, the vehicle only has 56,000 miles on it but the Boys at Gulfstream use a foam to attach the Bumpers to the chassis rail and that was coming apart and unsafe so I've fabricated a new Bumper support frame front and rear.

Does anybody know anything about the under floor hot air heating unit, I just need to figure out how to take it out as ours sounds like howling Cat on some unlawful substance !!!!

Many thanks to you all, I will contact Todd this week because we would like to become full members of the FMCA if possible, so you never know its possible a couple of Brits may turn up at one of your get togethers.

We'd love to rent a Motorhome and travel some of the US but its unbelievably expensive for us Brits, in fact I knew one couple who actually purchased one in the US, traveled for a year and then shipped it home to UK, the Motorhome paid for itself.

Best regards

Peterk

[WMMPAYNE]

On 5/18/2015 at 0:03 PM, obedb said:

Suggest a brake fluid flush if one hasn't been done in awhile. Brake fluid is hygroscopic. When the water boils braking force is sometimes all but lost. 

Realize this is a 2 yr old post, but felt an update was needed.

Discovered Castrol LMA (Low Moisture Absorption) Brake Fluid lots of years ago.  With my limo company, standard practice is a brake fluid flush every 2 years using Castrol LMA.  In addition to the LMA properties, it also has a higher boiling point.
As far as master cylinder rebuilds, NAPA generally inventories the rubber pucks.  A quick brake hone of the cylinder bore & replacement of the rubber & spring(s), followed by a bench bleed & refitting and your master cylinder is ready to give you trouble-free service for many more miles.