View Full Version : Dagenham 4 speed manual trans oil ?

Soft Taco 84
11-30-2016, 01:28 AM
Hi all, new here to the forum. I was curious to what type of gear oil is recommended for the dagenham 4 speed. Also, it's my understanding that I shouldn't use any gl-4 or gl-5 gear oil. I'm having a hard time finding a sure answer anywhere online. Thought y'all might know. Thanks!

12-04-2016, 08:54 AM
The service manual says that for a 30,000 mile service you "Check manual shift transmission lubricant level and add lubricant as required."

Lubricant: "Ford hypoid gear lubricant C1AZ-19580-B (SAE 80)."

This stuff would probably substitute: "Valvoline™ High Performance 80W-90 Gear Oil, (1 qt) is a thermally stable, extreme-pressure gear lubricant that withstands severe temperatures and shock loading while providing excellent anti-wear, anti-scuffing, rust and corrosion protection." "All hypoid differentials (conventional and limited slip) and manual transmissions in passenger cars, light trucks, sport utility vehicles, vans and heavy-duty trucks where an API-GL5 or MT-1 fluid is specified."


See: https://www.walmart.com/ip/23325574?wmlspartner=wlpa&selectedSellerId=0&adid=22222222227024665641&wl0=&wl1=g&wl2=c&wl3=40839205352&wl4=aud-261800282140:pla-78652275512&wl5=9051897&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035&wl11=online&wl12=23325574&wl13=&veh=sem#about-item

When I had my differential re-built I asked the mechanic what type of oil did he fill it with. He looked at me kind of surprised and said "just regular gear oil". That is probably fine because a Falcon is a "regular kind of car". :)

12-05-2016, 02:34 PM
I've always used whatever 80/90 gear oil I can buy off the parts store shelf. I don't know you have much choice unless you go high-end specially oil brands.

I've gotten really good with these Dagenham's too. If you've never been into one I've got a few posts on my "Crazy" thread about working on one of mine. I used to have them on both cars, but the one I built in this thread is now in my wagon. The one that was in my wagon is in the shed with about 4 other cores I've bought over the years. The wagon had the first one, which I had to do some creative machining on to use. It was still driving fine, but the one I built for in the Ranchero (now has a 289 and getting a T5) was the best of all the parts I had, so it was very nice.




These transmissions have common failure modes, but hopefully yours is holding up. Getting parts is hard and expensive. Made of unobtanium I'm told. I've found it far cheaper to by cores anytime I find one.