I was under the truck today and I believe I found those two square plugs. Also theres some other part that is right next to it and I am wondering what that is.

 

I was hoping you would post a picture that confirms your transmission is a New Process 435--thanks. Yes, those are the drain/fill plugs. The part to the left that I believe you are referring to is just a rectangular metal cover for the Power Take Off (PTO) port. Your transmission is not equipped with a PTO so the cover is installed in it's place. These transmission were used in F100's through F350's (Maybe even heavier trucks--ND can chime in on that). Often, a F350 dually cab & chassis truck may have had a hydraulic dump box installed and the PTO drive would have been used to drive the hydraulic pump. Very common on farm trucks--I was farm kid.

 

For me to confirm it is a np435 where would I take the pictures?

 

The pictures you have taken were good enough. We can usually tell by the way the cast iron housing is shaped compared to a Borg Warner T-18. The "435" on the ID tag also appears to confirm it.

 

Huh I never would have thought of it being a 435 based by the number on the tag , anyways would it be okay if I opened that pto cover so I could possibly see inside it and clean it if possible? Thanks.

 

This is the transmission ID tag, but it's so filthy I cannot make out the 2nd digit of the prefix. What I can read is C?TA-7003-AA

Warner T-18/T-19/T-98 4 speed: Spring loaded shift lever retainer cap (8MTH-7220) threads off/on.

NP435 spring loaded shift lever retainer cap (B8T-7220-D) has two notches, is retained to the shift tower with two pins.

To remove this cap, it must be pressed down by hand and held down while turning it counterclockwise to remove it.

Clueless people use pliers or channel locks to remove it, which tears out one or both of the notches. Not pleasant!

 

If you do open that, be ready to replace (or maybe make) that gasket. You can use diesel fuel, as a solvent, and a small paint brush to clean that tranny out. Or Brake cleaner.

 

I have Lucas Synthetic 75W-90 Gear Oil Trans & Diff Lube. Rated API GL-4, API GL-5, API MT-1, SAE J2360 (MIL-PRF-2102E, MACK GO-J, PG-2 Limited Slip. I just emailed Lucus to find out what they say about this product and it's corrosiveness to cooper and yellow metals.

 

PER; https://www.bobistheoilguy.com/forum...opics/509692/1
LINK >> Bob is the Oil Guy <<

QUOTE >>>>>>>
Re: GL5 and yellow metals: which spec is safe?
#509691 09/28/04 10:18 PMGrossomotto
Joined: Oct 2003
Posts: 296
Pablo said it right, "Modern GL-5 gear lubes will not harm brass"

I wouldn't use most 75W90 Synthetic GL-5 Differential Gear Lubes in a manual transmission. Although, you can and I doubt there will be any damage as a result. As you know, transmissions are very picky with the fluid used and many have proprietary blends like Toyota and GM.

Take Royal Purple Gear Max Synthetic (rated Gl-4 and Gl-5) for instance. You can use it in a variety of applications including front/rear diffs and manual trans. I've only used it in the diffs.

Other products from Redline, like their 75W90 Gear Oil, I would be careful with as well. Even their MT-90 (75W90) and MTL (70W80) manual trans fluids often have to be mixed 50/50 for good results.

This is from Redline (and may be outdated): <<<<<<Quote

 

The GL5 is the issue, you can't have a GL4 and GL5 rating on the same oil. Do a search on BITOG lots of reading. If you want the fluid that was in the transmission to begin with it's still sold and easily available at napa as part NHF 65201. That's a 90w GL1 gear oil (same viscosity as 50w engine oil) it has no EP additives and is yellow metal safe.

 

Oh now that gear oil should definitely be safe to use and probably more available than a 50w engine oil is nowadays.

 

Curiously, This oil says it "EXCEEDS" both the GL-4 and GL-5 ratings.

API GL-4, API GL-5, API MT-1 SAE J2360 (MIL-PRF-2105E,MACK GO-J, PG-2 LIMITED SLIP
LUCUS Synthetic SAE75W-90 GEAR OIL Transmission & Differential Lube

 

I did find the following info on the Web----

__________________________________________________ ________
Quotes and paraphrase from the article by Richard Widman Revision 6-2017


The Difference between GL-4 and GL-5 Gear Oils


GEAR OILS -YELLOW METALS-TRANSMISSIONS VS DIFFERENTIALS

"There is a lot of confusion about gear oils and the API classifications. In this paper I will try to differentiate the two oils and clear up the mysteries that are flying all over the internet. It is extremely common, or normal, for all GL-5 oils to claim they cover the API GL-4 requirements for gear oils. This is a true statement. Does that make them satisfactory for synchromesh or synchronized transmissions? NO! They meet the GEAR OIL specifications, not transmission oil specifications. The API GL-4 and GL-5 categories do not mention or have anything to do with transmission synchronizers.

History: The gear oils of a few decades ago had lead additives that were effective at wear reduction, but not very good for the environment. A long time ago they began to be replaced by gear oils with a phosphorous additive (in itself a decent anti-wear additive) with active sulfur to grip hold of the gears and create a very solid sacrificial layer of material that could be worn off, thereby protecting the gear surface. Eventually it was discovered that the active sulfur was causing corrosion of brass and other soft metals used in differentials and transmissions.

Somewhere around 25 years ago a deactivated or buffered sulfur was developed that would react with the phosphorous to create the protective/sacrificial layer in the conditions created in the gear boxes (temperature and pressure) without being corrosive to the brass, copper, etc. This additive system is used in most gear oils today. The problems arise when we try or need to use the same product in the transmission that we use in the differential.

Many people have called oil companies and been told by the “Techs” that answer their questions that their oils have buffered sulfur and therefore are not corrosive to yellow metals, so their GL-5 oils can be used with brass components. While that answer is totally correct, it does not address the question asked: Can I use your GL-5 in my synchromesh transmission? …

In normal operation, the sulfur/phosphorous additive forms a black sacrificial coating on the gears and anything it touches with a little pressure and temperature. As the gears turn, instead of wearing, the sacrificial coating of additives is peeled off or worn off. This is normal and acceptable in all steel gears. But when one or more of the surfaces is brass or another soft metal, the sacrificial coating is stronger than the base metal, and instead of just peeling off, it takes with it a few microns of the brass that it is bound to. …

A traditional GL-4 gear oil of any given viscosity has about ½ of the level of sulfur/phosphorous additive that would be in the GL-5 product, so the bond is not as strong, and therefore can be peeled off without peeling a layer of brass (or less brass). This means the GL-4 product provides a little less extreme pressure protection, so would not be ideal in the differential of a high-powered car. To understand this need we should be aware of the fact that the differential is where the final torque is applied to the wheels (in most applications).

But in the transmission, we should consider two factors:

• Due to the fact that the differential applies the final torque, normally we do not need the full EP protection in the transmission where less torque (about 30%) is applied.

• We need to be able to break the EP protection to stop the spinning of the gears long enough to mesh them or synchronize them.

When we use a GL-5 product in a transmission that requires GL-4, we normally find 2 to 4 times as much copper in the used oil when compared to a required GL-4 product (with used oil analysis). Eventually the synchronizers wear to the point that they no longer make contact with the other half of the cone, bottoming out before stopping the opposing gear.

Modern highly machined components require thinner oils and cannot tolerate sulfur/phosphorous additives in the oil, but rather depend upon friction modifiers, magnesium or calcium sulfonate, and often synthetic base oil which provide GL-4 or better performance.

Even though these additive packages provide better EP (Extreme Pressure) protection than a GL-4 sulfur/phosphorous oil, … most new formulations are way too thin for most classic cars

Although a modern GL-4 or a GL-5 Oil has buffers to reduce or eliminate corrosion of copper and yellow metals, they still may have so much binding power they do not allow the peeling off of the sacrificial layer alone. Therefore some GL-5 Oils are not recommended for transmissions where lower EP GL-4 Oils provide ample protection for reduced torque.
______________________________________________

NOTE: Would the following statement be the reason these newer oils are too thin for classic cars?

>>>>most new formulations are way too thin for most classic cars which generally have greater tolerances, that is, more space, where a thicker oil and sacrificial layer needs to fill the gaps. <<<

 

The above is true, it's why I gave you the Napa part number. Your other option is the redline MTL it's only for transmissions and has no EP additives. Skip the Lucas and anything that is GL5.

 

I want to say thank you to everyone who has given me more info about this truck and the fluids it takes, and also I do really appreciate it because now I know what to use in it.