SM 465 gear oil help

[murguia]

Looking to replace the gear oil in my 4 speed 68 but I’ve been reading not to use gl5, only 4, but it seems difficult to locate.


Hoping I can get some guidance on what to use

Thanks

[Sheepdip]

Originally Posted by murguia

Looking to replace the gear oil in my 4 speed 68 but I’ve been reading not to use gl5, only 4, but it seems difficult to locate.


Hoping I can get some guidance on what to use

Thanks

I run Lucas Full Synthetic 75W-90 in both my rear end and manual gear box.

[Sheepdip]

Originally Posted by Sheepdip

I run Lucas Full Synthetic 75W-90 in both my rear end and manual gear box.

Full synthetic oils contain no sulfur, any sulfur would be introduced via bio additives that contain sulfur.

I have been using Lucas Full Synthetic Gear Oil in all of my rear ends and manual transmissions practically since it came out with never a hint of a problem, superb performance.
Common to all synthetics that claim no posi additives required... I will call B.S. on that in my personal experience, I always add a tube and I have found the MOPAR to be the best.

[Richard]

Originally Posted by Sheepdip

I run Lucas Full Synthetic 75W-90 in both my rear end and manual gear box.

The custom D60 front axle I purchased for my truck from East Coast Gears had a tag on it that said "do not use full synthetic gear oil" Take it or leave it.

[Sheepdip]

Originally Posted by Richard

The custom D60 front axle I purchased for my truck from East Coast Gears had a tag on it that said "do not use full synthetic gear oil" Take it or leave it.

I'm sure they had their reasons.

[adf5565]

Yep Lucas oil has it

[murguia]

The Lucas I’ve seen is gl5 rated and in my research it seems it’s had some issues with my type of transmission and the softer metals….

Is this a valid concern, or am I maybe reading too much into it and Gl5 products will work just fine?

[murguia]

Was thinking of giving this a shot.

[72c20customcamper]

Sta-lube

NAPA carries it

[murguia]

Tried looking for that sta-lube but seems to be on back order at a lot of places, including my Napa and online

[adf5565]

Crap I misspoke. I purchased VP racing GL4 not Lucas. Here is the link.

https://vpracingfuels.com/product/vp...80w-90/?c=394&

[RichardJ]

GL5 is better than GL4 for gears in the rear end, but GL5 is bad for the brass syncros in the manual transmission. That doesn't mean GL-4/5.

Look for Sta-Lube GL-4 or Valvoline GL-4. Those are the ones I am usually able to find.

[murguia]

Thanks everyone

[murguia]

Anyone see any red flags with the triax I ordered on Amazon? Can always return and get something else.

GL4 and seems to be for synchronized…

https://www.amazon.com/Synthetic-Shi...ws_feature_div

[jeffahart]

Originally Posted by murguia

Anyone see any red flags with the triax I ordered on Amazon? Can always return and get something else.

GL4 and seems to be for synchronized…

https://www.amazon.com/Synthetic-Shi...ws_feature_div

I concur with HO455. Here's the verbiage from Novak: "When filling your 465 with gear oil, we recommend that you select a conventional mineral oil or a para-synthetic in lieu of a full synthetic oil.... "An 80W-90, API-GL5 or MT-1 rated fluid is very good."

Though I have 3 or 4 gallons of Sta-Lube GL4 on my shelf, If I did not, and with it being such a hassle to get GL4... I would just go with GL5 and be done with it.

My two cents. Good luck!

j

[PbFut]

I am not familiar with what you choose. A little late to the party. I ran a Jerico dog box in a road race application about 12 years. Refreshed every 2 years and oil changed at about 3 to 5 hours use.. Should have been more often but $$ always an issue. I experimented with 4 different oils. All 75-90. Thicker will affect you shift speed and ease of engagement, very critical for my use. Royal Purple was black. I did not like the results and feel it is a marketing product over real world result. Red line has a product that claims it fights gear crash. I bit, given critical for dog ring syncos It was ****. Mobil One performed quite well and price is decent. Hands down the oil that performed the best was Valvoline. It comes out as gold as it goes in. I use 75-140 in the diff. I do not have a cooler on the diff. It is a clutch style with ramps for the spider gears to walk on and tighten as torque is applied. Great for loosening in a corner, slipping the 5 clutches and then tightening down on corner exit. This allowed rotation in the corner and lock the differential on excelleration down the straight away. Lots of heat. The Valvoline 75-140 would pour in gold and out nearly the same color. I ripped a bunch of teeth off, and twisted splines but never a oil or heat failure. So Valvoline is my go to brand in all 4 of my cars and truck.

[Getter-Done]

My brother sent me a link to this Site Years ago.

This has lots of Information/Opinions about oil.

You have to Weed thru it though.

Link: https://bobistheoilguy.com/forums/

Also this link: https://www.tractorbynet.com/forums/...shings.145754/

The 90 weight oil was safe for Bronze and (Yellow metals) years ago when these trucks was in there 20's.

This new oil.

Can you go Wrong with Syntetic or GL -12345?

If you keep these transmissions filled with some oil that,
Doesnt leak out faster that you fill it they will be okay.

[MJN]

If you haven't made up your mind yet Amsoil offers 75W90 for manual transmissions, meets GL-4 rating and protects brass synchros. Its what I run in my 4-speeds too.
https://www.amsoil.com/p/amsoil-75w-...gear-lube-mtg/

[murguia]

Nobody has stated if they see any red flags with the one I bought, so I’m gonna be the test dummy and report back.

I appreciate all of the other info and recommendations.

[57taskforce]

I run GL5 in mine and have never had a problem.

[Bob B.]

The issue with GL-5 is that many GL-5 products have sulphur in them. The sulphur is to protect hypoid ring and pinion gears from scuffing wear, just as motor oil back in the day had sulphur in it to protect flat tappet lifters and camshafts. Same kind of wear. Sulphur however is corrosive to brass and other non-ferrous metals commonly used in some manual transmission synchonizers. That's why most manual transmission specified GL-4 because GL-4 does not have sulpher in it.

[murguia]

Just circling back to say the on I posted and bought has been working great!

[Getter-Done]

Response of Results is Always a Good Thing.