MTFCA Forum

What oil should I put in the rear end in my 1916 Model T? I sucked out the old and am ready to add the new.

I have used "pourable grease". I get this from a friend who has some of the largest cranes in the South East. He has used it in his car collection which includes T's, early Cad's, Stutz and etc. I have not had a problem with it in three of my T's for about ten years.

Non rux - 140 wt. This is what the rebuild manuals recommend.

speedytinc wrote: ↑

Mon Apr 11, 2022 1:57 pm

Non rux - 140 wt. This is what the rebuild manuals recommend.

He means, if you don't have a Ruckstell axle, use 140 wt. gear lube.

Alternatively there is a 600W rear differential lube favored by many. Either one should do the job <https://www.modeltford.com/item/600W.aspx>

I use this https://penriteoil.com.au/products/transoil-sae-250

I don’t know what some will say but I have used Lucas hub oil. My 26 has it in it I think.

When returning my barn find Henrietta to the road after her 66 year slumber I checked the rear axle oil level as part of the procedure. I was surprised to find no oil, but did ring a copious amounts of grease. I put the plug back in and have driven her for 4 years as is. It will be interesting to see how it looks when I do have to rear it down. Allan from down under.

Lang’s sells 600 weight gear oil for a standard T rear end.

Considering the old lube can be like molasses in February how do you ‘suck’ it out?

I've been using sae 140 in all of my Ruckstells for years.

Ned L wrote: ↑

Tue Apr 12, 2022 7:29 am

Lang’s sells 600 weight gear oil for a standard T rear end.

Considering the old lube can be like molasses in February how do you ‘suck’ it out?

I went to Harbor Freight and bought a Transfer hand pump for $6.99 it took a lot of pumping but I got it out.

Jerry VanOoteghem wrote: ↑

Mon Apr 11, 2022 8:30 pm

speedytinc wrote: ↑

Mon Apr 11, 2022 1:57 pm

Non rux - 140 wt. This is what the rebuild manuals recommend.

He means, if you don't have a Ruckstell axle, use 140 wt. gear lube.

now I understand what Non Rux is, thank you

While I'm not a big fan of other synthetics I have been using this in my Differential as well as my Warford and other antique gear boxes and rear ends. It has worked well for 20 years or so and I have not discovered any ill effects. You want to have good seals. It likes to creep out but the new style axle seals hold it OK.

Original Smith wrote: ↑

Tue Apr 12, 2022 10:04 am

I've been using sae 140 in all of my Ruckstells for years.

Any noticeable wear?

Gear grease, "pourable grease". gear oil, steam cylinder oil, oil or grease: just call it differential fluid so its not confused with engine oil or engine oil viscosity W
The Amsol & Penrite references seem aligned with the references to the differential fluid being 600W
SAE 140W gear oil appears to have a wide range of applicability and ISO 600 appears to be within its range.

From various sources
--
https://modelafordclub.co.nz/wp-content ... 0W-Oil.pdf "Everything I've found indicates 600W was mineral based gear oil, early Model T data talks about 600W Steam Cylinder Oil, which research showed having a viscosity of ISO600/ 680."

--
Penrite Transoil 250 is premium non EP, API GL-1 rated SAE 250 gear oil designed specifically for use in veteran, vintage and Edwardian gearbox, transaxles and selected spur and bevel type rear axles. It does not contain any aggressive load carrying additives that may cause corrosion damage to ferrous and non ferrous metal types used in these types of vehicles. It is suitable for use in rear axles of veteran cars of one, two and four cylinders. It contains a special additive to help the load carrying ability of the oil. Contact with any water or moisture should be avoided or seal degradation may occur. This oil is compatible with leather and synthetic rubber seals. Please Note: While this oil has the characteristics of the old 600W or steam cylinder oils, it MUST NOT be used as a steam cylinder oil.

I've been using this stuff for years in both Ruckstells and stock rear axles. The label states that it is non corrosive to bronze. I have no idea as to whether other gear oils might be but I'd rather play it safe as to the bronze thrust washers.

When it was time to pump out the old gear oil and put in something new, I strolled down to the local parts shop and went through their selection of gear oil. Almost everything was a multi-weight oil and I ended up selecting a Lucas oil 85w-140. I knew the 140 would be in the neighborhood of to 600 oil the T’s were recommended to have.

Would a multi-weight oil for the differential be considered similar to the common arguments on engine oil? As in, it’s a far better quality oil than anything they had back in the day, so you’re all good? Or does that multi-weight oil possibly pose a risk of not protecting your differential enough with the initial lighter weight characteristic of the oil? I believe a Model Ts differential is known to have a few drips… but I wonder if a multi weight oil results in excessive dripping as compared to a Lang’s straight 600 or SAE140 gear oil since it’s thinner when the T is parked for a while in a garage or parking lot.

Darin

This topic can go on for ever and everybody has their own formula, when Model Ts came out of the factory there was grease in the differentials, they never used any oil. There were no seals to prevent any leakage only dust covers to prevent dust from entering, so each to his/her own.

Grease comes in various weights from nearly liquid to almost solid from 000 up to #3. the differential housings did not have a drain plug only a fill plug, some early references call it an oil plug and many refer to it as a grease plug. Many have modified the differential housings and installed a drain plug, however a drain plug was never on the original housings. Some plugs were at the midway location and some near the top.

David, could that mean the grease in Henrietta's diff could be original? She has led a sheltered life, so it could be possible. All jokes aside, grease makes good sense to me.
Allan from down under.

What do you think would happen if you put the same grease in the differential that you put in the front of the driveshaft for the universal joint?

DHort wrote: ↑

Thu Apr 14, 2022 9:35 pm

What do you think would happen if you put the same grease in the differential that you put in the front of the driveshaft for the universal joint?

I think the gears would carve a groove through the grease and very little would work its way back onto the gears, and almost none of it would flow into the Hyatt bearings or the differential bearings.

I substituted grease for gear oil in my 1915 rear end years ago to see what it would do. I noticed a decrease in power

Jerry, if you saw the accumulated, solidified mass of dried lubricant and dirt which almost completely filled the brake drums on Henrietta when I fitted new lined shoes, you might change that observation. It was certainly creating some drag, but I seriously doubt grease in the pumpkin would have a detectable drag on power output.

Allan from down under.

The early reference material calls for #2 grease this was the middle of the road weight of grease and got the cars rolling down the road. In warm climates there would not be any issues but in colder climates lubrication may suffer some. The term that, were used was NON FLOWING GREASE.
In the day there were various standards for categorizing grease weights, however today the standard institute is the National Lubricating Grease Institute. Common grease weights used today are number 1.5 and number 2, with number 2 being most common in automotive stores. Marine stores do carry number 1.5 weight, it is better than the number 2.

A good test for nonflowing grease is to place some grease on a flat glass on a hot day and point it up like an ice cream it should just slump but not flow. With the tests I have done number 1.5 seems to be the better choice, however number 1 would be better but I was unable to find it. All the various weights of oil just flowed off the glass. Grease weights can be from 000, 00, 0, 1, 1.5, 2 and 3.
The ideal grease should have the consistency of creamy margarine and it should not flow out the end of the axles. Some people constantly say it will just cut a swath through the grease and not lubricate any thing. This would be true if you used too heavy a weight of grease, you can't just say grease and stop there. The proper weight must be used for the proper application.

The design of the Ford differential housings was to accommodate grease, there were no seals just dust covers. The outer bearings were lubed with grease cups, a heavier weight could be used for this application to reduce any run out. With a creamy non flowing grease in the housing the inner bearings would be adequately lubricated. The early reference calls for about 2 pounds of grease, there is no mention of "up to the bottom of the filler plug". Some filler plugs were at the top of the housing, some part way down and others in the center. For grease it didn't matter where the fill hole was. I have grease in my 15 and 26 and would not use anything else.

Ford did stipulate how much lube was required although it can be a little vague and what year owner manual you read. Early Canadian just says fill with grease every 2000 miles. An USA manual would say the diff is a 1/3rd full of fluid grease and checked every 1000 miles for a level being one and one half inches below the filler plug.
Canada lowered the plug level as early as 1915 for lube level with USA following in about 1919.

There are many posts and discussions about differential lubrication and various oils used and "never had a problem", There are also many discussions about leaking oil from axle housings and the various means to fix those leaks, what ever works for you and each to his/her own. When you take a good look at a T differential they are not designed for oil because they have no seals, just dust covers. In the days of the Ts, rear engine bushings wore out and engine oil migrated in to the differential housing and eventually out the axle ends. A quick fix was to stuff a wad of felt washer material into the housing to dam the oil from getting out, however the real problem was not fixed at this time this was just a patch job. As time passed this procedure became a rule and all the time it was only a quick temporary fix.

I replaced the oil(?) in my rear end with the product Lang's sells. My once noisy rear end is now quiet.

The 600 would be fine in a stock rear axle. It should quiet it down and still lubricate. However too stiff to flow into all the inner parts of a Ruckstell. The 140 should work fine in a Ruckstell.
Norm

Allan wrote: ↑

Fri Apr 15, 2022 7:56 pm

Jerry, if you saw the accumulated, solidified mass of dried lubricant and dirt which almost completely filled the brake drums on Henrietta when I fitted new lined shoes, you might change that observation. It was certainly creating some drag, but I seriously doubt grease in the pumpkin would have a detectable drag on power output.

Allan from down under.

????

I never said anything about drag.