2wd SM465 Speedo Gear Problems

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WFO

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This is the only GL-4 lube that I've been able to find for the last few years.
Been running it for several years in my SM465, and in the Super T-10 in my Chevelle.

 

Powerhouse Ranch

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This is the only GL-4 lube that I've been able to find for the last few years.
Been running it for several years in my SM465, and in the Super T-10 in my Chevelle.

i really like this man. do you have to add anything else? Does it keep your SM465 pretty quiet? -Thanks

P.S. You're the flippin man
 

WFO

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i really like this man. do you have to add anything else? Does it keep your SM465 pretty quiet? -Thanks

P.S. You're the flippin man
Yeah, it's pretty quiet, and no additives. It is a little stiff gettin into gear on a real cold mornin until it gets up to temp. Doesn't do that on my T-10 though.
 

Powerhouse Ranch

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Yeah, it's pretty quiet, and no additives. It is a little stiff gettin into gear on a real cold mornin until it gets up to temp. Doesn't do that on my T-10 though.

well **** i don't even drive my truck in the winter. TOO CLEAN FOR PA SALT!

Thanks again man, already ordered it up. If my truck ain't happy, neither am i.
 

AuroraGirl

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so GL-5 barely misses it? My dad's been around Squares his whole life, and when i held up 80w-90 GL-5 he signed off on it. It's that much of a difference?
I dont know if you would be able to notice a difference. TBh I have GL-5 in my sm465 but i can assure it was a far better fluid than the stuff I pulled out. The stuff that came out separated to 2 distinct fluids, but one wasnt water......

It made it a lot quieter and seemingly better but I dont drive at speed or engage the 2/3 synchros (3 being the problem child I think?) , so I wouldnt be the representative person on that. I just remember reading here over a year ago that the metals are properly protected, brass and bronze that is, with gl-4 and GL-5 is more aggressive. If that means chemically or physically Im unsure. I would assume the yellow metals being softer than the other metals around them and most gearboxes these days not using brass or bronze to my kwowledge, the formulation just doesnt account for them. I recall using my owners manual for my 1980 to look and I do believe it said gl-4.

I just checked my 1980 owners manual, it says 80w-90 GL-5 for manual trans, no special notes. it says if in canada, use 80w GL-5
also it gave the otpion for a non multigrade GL-5 before the 80w90 but I forgot what it was. something with just one number or something.

Anyway, so I guess i am unsure. @bucket you are knowledgeable on Gear Lube can you learn us the answwer


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I looked into a 1986 FSM just to due dilligance(since my trans isnt a 1980 in the truck) and the same data... SORTA. It indicates to use a Dexron II(cant buy that anymore, so unless you want some used Dex II from my 1990 oldsmobile (well used) then DexIII would be the only available similar fluid that "retroactively" works in its place.

I would suspect this is for economy and shifting ease, maybe? I dont know how I feel about using an ATF in a SM465.

But it looks like the NP205 has this change too... curious about how good it is for them..


Anyway. I am unsure now. Mt1 additive is something I found on a quick search, something about avoiding GL5 if has limited slip additives, and something about synthetics... but it seems there is a consensus that either old transmission oriented products or ones that use MT1 additive (for the brass and stuff) is the best route, and that means you could have GL4 or Gl5. But I just literally googled that in like 3 minutes. So.
 

Powerhouse Ranch

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I dont know if you would be able to notice a difference. TBh I have GL-5 in my sm465 but i can assure it was a far better fluid than the stuff I pulled out. The stuff that came out separated to 2 distinct fluids, but one wasnt water......

It made it a lot quieter and seemingly better but I dont drive at speed or engage the 2/3 synchros (3 being the problem child I think?) , so I wouldnt be the representative person on that. I just remember reading here over a year ago that the metals are properly protected, brass and bronze that is, with gl-4 and GL-5 is more aggressive. If that means chemically or physically Im unsure. I would assume the yellow metals being softer than the other metals around them and most gearboxes these days not using brass or bronze to my kwowledge, the formulation just doesnt account for them. I recall using my owners manual for my 1980 to look and I do believe it said gl-4.

I just checked my 1980 owners manual, it says 80w-90 GL-5 for manual trans, no special notes. it says if in canada, use 80w GL-5
also it gave the otpion for a non multigrade GL-5 before the 80w90 but I forgot what it was. something with just one number or something.

Anyway, so I guess i am unsure. @bucket you are knowledgeable on Gear Lube can you learn us the answwer


You must be registered for see images attach

I looked into a 1986 FSM just to due dilligance(since my trans isnt a 1980 in the truck) and the same data... SORTA. It indicates to use a Dexron II(cant buy that anymore, so unless you want some used Dex II from my 1990 oldsmobile (well used) then DexIII would be the only available similar fluid that "retroactively" works in its place.

I would suspect this is for economy and shifting ease, maybe? I dont know how I feel about using an ATF in a SM465.

But it looks like the NP205 has this change too... curious about how good it is for them..


Anyway. I am unsure now. Mt1 additive is something I found on a quick search, something about avoiding GL5 if has limited slip additives, and something about synthetics... but it seems there is a consensus that either old transmission oriented products or ones that use MT1 additive (for the brass and stuff) is the best route, and that means you could have GL4 or Gl5. But I just literally googled that in like 3 minutes. So.

Oh god i'm so confused now! @hoagster suggested to me CRC 85W-90 gear oil GL-4, says he's been using it in his SM465 with no problems. Sent me a link and i pulled the trigger.

I already got a quart in the mail and the gallon could take up to the 22nd, so i ordered a gallon of the same stuff from my local NAPA and should be able to pick it up tomorrow. So i currently have the GL-5 80W-90 in her now but i'll drain that real good tomorrow morning and hopefully have a full, happy GL-4 transmission. If i still have a noisy tranny, we're going to have to have a serious think-tank!
 

AuroraGirl

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Oh god i'm so confused now! @hoagster suggested to me CRC 85W-90 gear oil GL-4, says he's been using it in his SM465 with no problems. Sent me a link and i pulled the trigger.

I already got a quart in the mail and the gallon could take up to the 22nd, so i ordered a gallon of the same stuff from my local NAPA and should be able to pick it up tomorrow. So i currently have the GL-5 80W-90 in her now but i'll drain that real good tomorrow morning and hopefully have a full, happy GL-4 transmission. If i still have a noisy tranny, we're going to have to have a serious think-tank!
where in countyr you at again ? North dakota? The "canada" spec of fluid I would say would be worthwhile if you either 1) are dilligant and change fluids often, maybe even 2 times a year once before summer once after
2) Want it to shift the easiest as it can in COLD COLD temps
3) dont plan to use it for HD **** like you arent pullign a 28k trailer in 4hi OR ANYTHING(thats exaggeration)
4) you dont plan to use it hard when its hot-hot. Like me, I would probably benefit from a lighter fluid(i should put the right stuff in anyuway, of course, so it protects synchros) but if I was using it for farm stuff and did a lot of slow-heavy moving in the summer, that fluid would get thinner than...
paint thinner.. best analogy i could think of lol.


If you plan to all-around use it, honestly your plan is a great one(the stuff coming) and hey it never hurts to "flush" something once in a while pending exceptions*

Because reverse and Low got a lot of use from me, and 1st only a bit more than those (while plowing) i probably have harmed very little using supertech 80w-90 (i got it in those little quart bottles)

but I should check my mystik 5 gallon pale with a pump on top, I didnt know i had it till long after this maintaince i referenced, But if its the right stuff I can easily pop the drain, dump it, and pump it quikcer than it took to take the drain off, and maybe do the front and rear axles while at it.

and the trailer, teh trailer is due for new fluid and fix the vent
 

hoagster

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Oh god i'm so confused now! @hoagster suggested to me CRC 85W-90 gear oil GL-4, says he's been using it in his SM465 with no problems. Sent me a link and i pulled the trigger.

I already got a quart in the mail and the gallon could take up to the 22nd, so i ordered a gallon of the same stuff from my local NAPA and should be able to pick it up tomorrow. So i currently have the GL-5 80W-90 in her now but i'll drain that real good tomorrow morning and hopefully have a full, happy GL-4 transmission. If i still have a noisy tranny, we're going to have to have a serious think-tank
I don't know how my name got in the transmission thread for gear oil. I don't even have a thread saved for crc gear oil.
 

WFO

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where in countyr you at again ? North dakota? The "canada" spec of fluid I would say would be worthwhile if you either 1) are dilligant and change fluids often, maybe even 2 times a year once before summer once after
2) Want it to shift the easiest as it can in COLD COLD temps
3) dont plan to use it for HD **** like you arent pullign a 28k trailer in 4hi OR ANYTHING(thats exaggeration)
4) you dont plan to use it hard when its hot-hot. Like me, I would probably benefit from a lighter fluid(i should put the right stuff in anyuway, of course, so it protects synchros) but if I was using it for farm stuff and did a lot of slow-heavy moving in the summer, that fluid would get thinner than...
paint thinner.. best analogy i could think of lol.


If you plan to all-around use it, honestly your plan is a great one(the stuff coming) and hey it never hurts to "flush" something once in a while pending exceptions*

Because reverse and Low got a lot of use from me, and 1st only a bit more than those (while plowing) i probably have harmed very little using supertech 80w-90 (i got it in those little quart bottles)

but I should check my mystik 5 gallon pale with a pump on top, I didnt know i had it till long after this maintaince i referenced, But if its the right stuff I can easily pop the drain, dump it, and pump it quikcer than it took to take the drain off, and maybe do the front and rear axles while at it.

and the trailer, teh trailer is due for new fluid and fix the vent

Mystik JT-7 Multi-Purpose Gear Lubricants are multi-purpose, thermally stable, sulfur-phosphorus extreme pressure (EP) gear lubricants that exceed the performance requirements of the latest axle and non-synchronized manual transmission specs, SAE J2360 and Mack GO-J. A specially balanced additive provides thermally stable gear lubricants with exceptional durability under high temperature conditions.
 

Turbo4whl

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Oh god i'm so confused now! @hoagster suggested to me CRC 85W-90 gear oil GL-4, says he's been using it in his SM465 with no problems. Sent me a link and i pulled the trigger.

I already got a quart in the mail and the gallon could take up to the 22nd, so i ordered a gallon of the same stuff from my local NAPA and should be able to pick it up tomorrow. So i currently have the GL-5 80W-90 in her now but i'll drain that real good tomorrow morning and hopefully have a full, happy GL-4 transmission. If i still have a noisy tranny, we're going to have to have a serious think-tank!

So Luke, before you drain and change the oil, why don't you fix the speedometer? I realize that some of my posts may confuse people, because they have info that is not in any book or even online.

The information comes from 50 years of working on fleet trucks. Sometimes to get the required results you need to re-engineer a part or two. If I make a statement that seems like I am out in left field, it is because I have seen the same problem and offer a fix that I know will work.

Loctite the drive gear on the output shaft. Isn't that why you got into the trans to start with?
 

AuroraGirl

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Mystik JT-7 Multi-Purpose Gear Lubricants are multi-purpose, thermally stable, sulfur-phosphorus extreme pressure (EP) gear lubricants that exceed the performance requirements of the latest axle and non-synchronized manual transmission specs, SAE J2360 and Mack GO-J. A specially balanced additive provides thermally stable gear lubricants with exceptional durability under high temperature conditions.
You must be registered for see images attach

Whichever that one is yes
 

AuroraGirl

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So Luke, before you drain and change the oil, why don't you fix the speedometer? I realize that some of my posts may confuse people, because they have info that is not in any book or even online.

The information comes from 50 years of working on fleet trucks. Sometimes to get the required results you need to re-engineer a part or two. If I make a statement that seems like I am out in left field, it is because I have seen the same problem and offer a fix that I know will work.

Loctite the drive gear on the output shaft. Isn't that why you got into the trans to start with?
if he wasnt tied to his cluster or speedo specifically much I would go for a nice quality GPS speedo but that is a lot of work on its own just in the cab not under it. all I know is a GPS speedo in 2 1/16 size is... not common. Cost a lot to get specially made too lol
 

Powerhouse Ranch

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OKAY, MAJOR UPDATE FOR EVERYONE!
@Turbo4whl
@AuroraGirl
@hoagster

Few things, first, sorry Mike, i meant to say @WFO , he's the one that gave me the gear oil idea haha. SO ANYWAY, about a week ago when i put the whole tranny back together with everyone's thoughts in mind, i CONFIRMED that when the output flange was screwed back on the output shaft with the tailhousing, it did indeed tighten the drive gear against the tranny on the output shaft, eliminating all movement, except for that intended. Everything else went back together right, new gasket, new seal, new fluid. First i made the mistake of filling it with 80W-90 GL-5. I test drove it and the transmission was very noisy. nothing bad i figured but something wasn't agreeing, and i didn't take it apart enough to have messed with anything. After more questions, WFO suggested 85W-90 GL-4 CRC gear oil, which i promptly ordered and wasn't going to get until like the 22nd or 23rd of the month. Figured that was wayyyy to long, got it off of my local NAPA this morning, God bless them for working on a Sunday and having such a fluid for me. Dropped the GL-5 and put in the GL-4. Still ran noisy at first but smoothed out. Everything runs like a charm and is all buttoned up from my recent repairs, NO LEAKS! (i swear, i'm always leaking oil, i've leaked power steering, tranny, rear end, and now my rad a little on the side haha)

SO then comes the mighty speedo problem! I had officially solved the issue today with the help from the old man. We were able to easily take out the speedo gear that the cable works with directly. Pulled it out, put some light on it and everything was MINT. He goes to put it back together and looks closer. GET THIS: So the actual little cable IN the speedo cable is square on the end right? Then that goes into the speedo gear. Well the opening of that gear is only square for so far. So the cable actually goes deeper into the gear, to the point in which it's not engaging anymore; the square portion of the cable isn't in the square portion of the gear. He was able to rig it and it worked for a few miles, but it quickly slipped deeper again. Now he's one to save things, instead of buying new. Suggested taking the topside of the cable off at the Speedometer and shimming it somehow so it wouldn't slip in the gear again. Thinking i might just get a new one. I don't know if it was the wrong one, or if it just got worn? I honestly don't know.

ALSO, today is my 2 year anniversary of my truck ownership!!
 

Powerhouse Ranch

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She's been running really good. Even taking the colder weather pretty good. Today the second half of my speedo cable should get here, and i'll be pulling my dash bezel and replacing on that. Hopefully ending the reign of the faulty speedo!
 

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