87 L8000 7.8 Ford Diesel. 5 speed and single rear axle gear (no high/low). 39,000 GVWR.

I recently purchased the old fire truck and I have done a lot of work getting it ready for the road (tires, brakes, oil pan gasket, belts, batteries, etc.) Since there was no service record book I am replacing the fluids and doing many maintenance items so I have a good base line.

What weight gear oil for transmission and rear axle? 85w90? 140? Will be used as farm truck and infrequently. Where can I find it in the 5 gal bucket? I went to the local farm supply and they only sell it in the quarts.

Any recommendations for a gear oil pump for filling?

 

did some searching and looks like 50wt oil.

 

50w was recommended for some older 4 speeds, and perhaps the 5s in older trucks.

It was never recommended for differentials.

Can you post your VIN and the info off the warranty plate? Lots of info available there, including the make of your trans.

A bit on trans and diff oils:

Synchromesh Manual Transmission Lubricants - Bob Is The Oil Guy

 

No VIN has codes related to trans or axle, both codes printed on Certification Label (1980 to date). Stamped on 1961/79 Warranty Plate and 1948/60 Rating Plate.

 

fyi This number has helped me in the past for lubrication questions.
800-237-8645 I think it's Shell Oil Co.

 

Eaton trans and axle? They have PDFs posted on their axles w/ lube info.

http://www.dana.com/wps/wcm/connect/...df?MOD=AJPERES

They have many more available on line. Search your needs.