Gear oil
Thread Starter
|
Senior User
Joined: Aug 2012
Posts: 113
Likes: 0
From: Phoenix
Gear oil
I know this is a stupid question, but I know someone can help me on here. I have a 62 f100 with a four speed manual transmission w/ granny. It has been shifting a little rough this morning and I'm wondering if there is a place I can check the gear oil if that's a possibility. I just had the rear differential worked on and there aren't any leaks there. Any help with this would be much appreciated.
Laughing Gas
Joined: Sep 2003
Posts: 968
Likes: 5
From: Corbett, Oregon
There should be a 1/2" pipe plug about mid way up on the side of the trans main case. Passenger side if memory serves me. This plug should have a 9/16" or 5/8" square end on it.
This plug is the fill hole and where you check fluid level. Remove the plug, stick your finger in and see where the fluid level is. If the level is within 1/2" of the bottom of the fill hole I call it good. If lower, fill to the bottom of the threads and put the plug back in.
Colder weather can cause for harder shifting, but seeing as you are in the Phoenix area, weather you call cold shouldn't affect the trans.
Good luck.
This plug is the fill hole and where you check fluid level. Remove the plug, stick your finger in and see where the fluid level is. If the level is within 1/2" of the bottom of the fill hole I call it good. If lower, fill to the bottom of the threads and put the plug back in.
Colder weather can cause for harder shifting, but seeing as you are in the Phoenix area, weather you call cold shouldn't affect the trans.
Good luck.
Thread Starter
|
Senior User
Joined: Aug 2012
Posts: 113
Likes: 0
From: Phoenix
Trending Topics
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
I would check the manual and find out what FORD specified back in the day, and then use whatever the closest equivalent is today. They may have used straight 50 wt motor oil back then, for example.
I've been using 75/90 for years in a three speed. Probably the wrong stuff, no problems afaik though.
I've been using 75/90 for years in a three speed. Probably the wrong stuff, no problems afaik though.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
3 Best / Worst Features Of The 2025+ Ford Expedition
Brett Foote
10 Ways Ford is LOSING to the Competition
Joe Kucinski
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
Senior User
Joined: Nov 2013
Posts: 106
Likes: 0
Great info on the T-98 can be found here: The T98 Transmission - Novak Conversions
Look at the bottom of the page at the grey box and the recommendations regarding the proper oil for these transmissions. I used their advice after I worked on my t-98. Here is the product from NAPA that I used. http://www.napaonline.com/Catalog/Ca...201_0434862994
Here is the quote from the page.
"When filling your T98 with gear oil, we recommend that you select a conventional mineral oil or a para-synthetic in lieu of a full synthetic oil. Properly assembled manual gearboxes do not have the thermal strains seen by combustion engines or hypoid gears. Synthetic fluid in these gearboxes, while not harmful, is probably an economic waste.
Hypoid gear oil is sulphurized higher than transmission oil and can be mildly corrosive to the non-ferrous alloys used for synchros, bushings and thrust washers in these transmissions.
An 80W-90, API-GL5 or MT-1 rated fluid is very good. Some claim faster shifts from using a 50W engine oil in their transmission and we do not consider this to be contraindicated unless you operate your vehicle in a very warm environment."
Look at the bottom of the page at the grey box and the recommendations regarding the proper oil for these transmissions. I used their advice after I worked on my t-98. Here is the product from NAPA that I used. http://www.napaonline.com/Catalog/Ca...201_0434862994
Here is the quote from the page.
"When filling your T98 with gear oil, we recommend that you select a conventional mineral oil or a para-synthetic in lieu of a full synthetic oil. Properly assembled manual gearboxes do not have the thermal strains seen by combustion engines or hypoid gears. Synthetic fluid in these gearboxes, while not harmful, is probably an economic waste.
Hypoid gear oil is sulphurized higher than transmission oil and can be mildly corrosive to the non-ferrous alloys used for synchros, bushings and thrust washers in these transmissions.
An 80W-90, API-GL5 or MT-1 rated fluid is very good. Some claim faster shifts from using a 50W engine oil in their transmission and we do not consider this to be contraindicated unless you operate your vehicle in a very warm environment."
Last edited by Jim Beckers; Jan 15, 2015 at 09:55 PM. Reason: Added info.
Logistics Pro
Joined: Mar 2005
Posts: 3,771
Likes: 80
From: tujunga, calif
I've read numerous articles in the past that recommend not using GL5 in transmissions that have soft metals like brass. I've stuck with GL4 to be on the safe side.
Laughing Gas
Joined: Sep 2003
Posts: 968
Likes: 5
From: Corbett, Oregon
Lubricant technology has changed a lot in the last 50 years, but I always use the factory recommendations as a good starting point. What works in a 2015 truck may not work in a 1965 truck, due to different materials, clearances, etc.
Logistics Pro
Joined: Mar 2005
Posts: 3,771
Likes: 80
From: tujunga, calif
I had a new 9" third member built for my 57 by a reputable company that only does rear ends and I have used many times in the past and they told me there is no problem using GL 5. I also inquired about Royal Purple Synthetic that I planned on using he told me that was fine also..
My 60 and 66 have StaLube GL 4.
My 60 and 66 have StaLube GL 4.
Thread
Thread Starter
Forum
Replies
Last Post
49m47
1948 - 1956 F1, F100 & Larger F-Series Trucks
10
Mar 25, 2014 02:53 PM
MONAVIERONJON
1994.5 - 1997 7.3L Power Stroke Diesel
15
Oct 7, 2010 09:40 PM
mybrownie
Clutch, Transmission, Differential, Axle & Transfer Case
4
Aug 31, 2009 10:38 PM
dennisb56
1948 - 1956 F1, F100 & Larger F-Series Trucks
17
Jun 8, 2008 08:04 PM