Hey everyone I have a 1969 f250 360 4 speed thats been sitting for a while and I am looking to do some maintenance on it, fluids to start off with. With the transmission its a 4 speed I dont know what model it is exactly, and I would like to know if I should use 50w engine oil for the tranny since thats what it maybe came with from the factory. Also for the rear end I dont know what weight gear oil or possibly engine oil it uses either.. I can take pics of both if need be to find out. Also the engine oil, I think it is a 360 and I want to know what oil weight to use and capacity as well thanks.

 

OK, about the tranny oil, in Volume4, page 19-03-30 of the 69 Ford Shop Manual, it shows to use SAE 50 (Gear Oil). My Chilton shows to use Hypoid 90 Gear Oil above 32 deg ( I guess that will be fine for a CA truck) or Hypoid80 below 32 deg.
In the rear diff, the BOTH manuals show Hypoid 90. But you have to keep in mind that oils have progressed 10 fold from 50 years ago. So, many people use 70-140, or 90-140 Gear oil. What ever you use, I would suggest a synthetic oil, they take less power to move, because they flow easier. And they take much more abuse and heat.
On the engine, 10w-40, or 10w-30 should be fine. Which brand is up to you. I prefer Mobil One. Some people even use the diesel truck oils because of the higher Zinc content. The engine will take 5 Qts and the filter another 1 Qt. It has been been suggested to add an additional 1Qt to the engine (the engine oil pan has plenty of room for it) to prevent the chance of oil starvation (I do this too). The extra quart should assist with cooling some too.

 

Warner T-18: Reverse is up, towards the dash.

New Process 435: Reverse is down, towards the seat.

 

Alright yeah mine is towards the seat, is there any difference besides that?

 

Thank you for the information also I checked around and found this in my glovebox for it and it showed that it used sae 50 engine oil for the transmission instead...

 

NumberDummy, this brings up an interesting question. I believe that at some point the T-18's shift pattern was switched to reverse down towards the seat. I do have a 1976 F100 and two 1979 F150's with T-18's--all have the original transmissions with reverse down and towards the seat. They are definitely T-18 transmissions since they have the cast iron top and threaded shifter retainer. I have seen the earlier T-18's in 1967 F100's (and I believe a 1969 as well) with the shift pattern as you stated (reverse up towards the dash. Do you know what year the shift pattern would have changed?

I apologize to the OP for a mini-hijack of his thread. I though it might be a good opportunity to try and pinpoint when the shift pattern changed for the T-18 so that fellow members don't assume that all T-18's have the reverse up towards the dash shift pattern.

 

T-18 shift pattern changed circa 1973.

 

I am wondering where I would find the fill and drain bolts for it.. I can show you pictures of it if need be.

 

Going from memory on this. I only have one of the trucks here tonight and it is -30C outside so I won't be crawling under it for some time.

The fill and drain plugs (not bolts) are standard NPT square headed plugs. They are approximately 1/2 inch plugs. They will be the only square headed plugs on the transmission. The drain plug is near the bottom (says captain obvious) and the fill plug I recall being on the passenger's side approximately half-way up the case. They are very easy to spot. If it helps you can post your pictures and myself or one of the other members will gladly identify them for you.

As for lubricant requirements, these transmissions don't seem to be particular about the viscosity. I have ran 80W90 non-synthetic gear oil in my T-18's for years (As previously mentioned its -30C here tonight). I didn't actually realize until a few years ago that Ford recommends 50W for these transmissions. My highest mileage one has 380,000 miles on it and has never been rebuilt--it still works like the day it was new. IMO, replacing the gear oil periodically is more important than the viscosity. I replace the gear oil every 60,000 miles. If you are going to replace it, put in the 50W for peace of mind.

 

Alright will do thank you, was planning to use 20w50 and filling it right up to the fill plug and let the excess drain out, also is there a transmission filter for it as well?

 

No there is no filter because there is no pump. Using 20w50 engine oil is a terrible idea also. There is straight 50w engine oil that meets the requirements of transmissions and is used in heavy trucks but it's not common place anymore. You can't use a multi viscosity oil in a transmission because you won't hit the 100cst target point for the viscosity improvers to do their job. You should use a GL4 rated or MT1 rated gear oil.

 

Hmm alright I was thinking of the 50w conventional oil from valvoline possibly instead of the mult weight and since ford recommended it, otherwise 80w90 gl4 gear oil will be going in or I will test out both!

 

The reasons I'd always heard stated for the use of motor oil instead of the gear lube of the same era (whichever GL number they were using at the time) was to help the soft metals (bronze mostly I would assume) live longer. The additives in gear oils were detrimental to the soft "yellow" metals.
The motor oil happened to work very well in those cases, but in the interest of the simplicity fewer different lubricants, I long ago started using the same synthetic 75w/90 gear lubes in all four of my gearboxes (both diffs, transfer case and transmission) to very good effect. But ONLY oils specifically stated on the bottles (or by the manufacturer) to be compatible with bronze in the form of thrust washers and blocking rings and such, and still good for differential's needs.
And it was also handy that the 75w/90 stuff was very thin and easy-flowing when filling the box. You could tell immediately when you started to pump it with the same gear lube pump I'd been using for other fills. The pumping was easily half as hard as with regular gear oils. Felt almost like motor oil.

So if you do change from a motor oil to a gear oil, just make sure that whichever one you choose says it's compatible with all the things you want it to work with, and then you can use the same one in all of your gearboxes as well.

Paul

 

80w90 gear oil and 50w engine oil are the same at 100cst. Avoid GL5 gear oil as it will eat bronze and brass. Oils that are rated GL4 are Compatible and so are all MT1 oils. I use Redline MTL because it's easy to get and gives nice cold shifting.

 

Alright I will keep that in mind when I go shopping for it.