M1078 Trans filters

[BigMontana]

Well group 55 are C3 pressure faults so something is going on with pressure or sensing that pressure.

that temp light is a programmed output generated by the controller and based off of its internal temperature sensing circuitry(sump temp sensor on the control module). The manual says it is supposed to illuminate when sump temp reaches 225F

Do you hear the engine fan kick in when coolant goes over 205F? They are louder than hell and hard to miss…

The P6 roller thrust bearing is all the way back under the rear top cover on the trans. Any parts will wind up down in the transfer case, and should find their way to the magnetic drain plug. That is how this is usually detected, parts found when transfer case oil is drained. It is not a very substantial roller thrust bearing so I don’t think it has enough parts to foul the transfer case scavenger pump Strainer. That is a secondary pumped loop that moves fluid from transfer up to main sump(probably for cooling), so not sure how it would effect overall transmission cooling. The transfer case might get warmer though…

Yes, the main fan comes on at between 205 and 215, it previously was not always coming on or not always coming on at full speed because there was an intermittent leaky air seal at the fan clutch, but i fixed that two days prior to this issue. at some point i will have that fun cut out switch turned into a three position switch: on, auto, off, it's nice to pre-cool before a hill pull, and is also nice to turn the fan on for no reason on the way down a hill for some extra holdback (fan is about equivalent to 1/3rd power jake brake).

There is zero fluid pressure i'm told, which would make sense as to why the trans was overheating and the main coolant was not. 225 is not terrible for a trans. i'm glad they put that light before a truly critical temp...I've run lots of axles and stuff right up to 235 and held them there for hours at a time...of course that's out of necessity on a half day mountain pull and i'm not going to be abusing a 1994 like that, but still i'm happy the warning hits at 225.

the oil inside the trans still has viscosity, and does not smell burnt, but there is quite a bit of metal flake in both the drained oil and the oil filters (shiny bits in the oil that you can see when you tilt the drained oil into sunlight, and shiny bits on the filters, this oil has only been used for about 2000 miles, and whatever oil remained after my half ass flush and filter change before leaving was 3 years and 700 miles old, and tested okay-ish via the cat fluid analysis lab.

It's looking like it'll be a more significant project than a few days here with the trans, and if i'm going to fix it, I'll try to fix it in a way that is a bit of an upgrade. make sure nothing goes wrong in this same area for a while.

I'm in Houghton, MI and a lot of float planes seem to be landing on the river here, another major stop for float planes is Ft. Benton, MT, not all that far from Polson and about 1200 miles from Houghton, MI, so maybe when it's time to get back here and drive it home i can find someone headed this way in a private float plane...cause there's not much for public long distance transportation up here.

Now i reckon would also be a decent time to switch to ATF instead of 15w-40 once i get a rebuild/rework or replace.

For now, back to bar study...because the pay difference between passing the bar exam and not is about $12k/yr and the next bar exam is Feb, so i'd prefer to pass in July (and find out in mid Sept).

 

[BigMontana]

There is a catch screen on the line from t case to scav pump. Take the line off the t case then you can unscrew the catch and see if any debris. If your t case bearing failed there will be bits of it there. It sounds like you dont have fluid pressure in the trans for some reason. Maybe bad torque converter. You can take it to an allison shop there are pressure test ports on the bottom of the solenoid pack.

Yeah, allison recommended the mechanic i am at, and one of the options i'm considering is just pulling the entire thing shift pad included and sending it to allison and having them deal with it. although i do see MME or one of those dealers has a full trans/transfer case reman for like $14,000, that wouldn't be bad especially if i could change the gear ratios a bit...it's gonna be a mostly offroad truck, but i wouldn't mind doing the eco hub thing which results in half RPM per operating speed at gear, and then maybe having a transfer case mod that results in a hair less than double RPM per in gear speed. my general goal would be cruise at 55 MPH at around 2,200 RPM, that's all the faster I'll ever need to go in this.

I'm not sure how much the eco hub conversion costs, but if it's all that expensive a welder ought to be able to do the exact same thing for pretty close to nodda.

 

[wheelspinner]

I'm not sure how much the eco hub conversion costs, but if it's all that expensive a welder ought to be able to do the exact same thing for pretty close to nodda.

My buddy and I were just talking about this. I actually have a set or Eco Hubs here and may do a set with the Lincoln Locker method to compare.

 

[Ronmar]

The problem I see with the locker method is the inner fixed gear is also the retainer for the wheel nut. Since it is fixed to the splined end of the hollow spindle, it must be removed, and something else used to retain the wheel nut, or it, and/or the spider gears must be very heavily modified to allow the now welded spider gears to pass its teeth without contact…

 

[GeneralDisorder]

The problem I see with the locker method is the inner fixed gear is also the retainer for the wheel nut. Since it is fixed to the splined end of the hollow spindle, it must be removed, and something else used to retain the wheel nut, or it, and/or the spider gears must be very heavily modified to allow the now welded spider gears to pass its teeth without contact…

Exactly. Waste of time to even consider wrecking a bunch of parts by welding all over othem when a tested product is available to do it the right way. The hubs pay for themselves in ~3500 miles just in fuel savings. If you can't afford to do it the right way then these aren't the trucks for you and you'll fail on many more levels trying to cheap out like that. Those kinds of decisions are what lead to fatal accidents when you are working with 20k lb+ heavy equipment.

 

[BigMontana]

Reply deleted to move the conversation to PM where it belongs.

Those kinds of decisions are what lead to fatal accidents when you are working with 20k lb+ heavy equipment.

 

[GeneralDisorder]

The problem I see with the locker method is the inner fixed gear is also the retainer for the wheel nut. Since it is fixed to the splined end of the hollow spindle, it must be removed, and something else used to retain the wheel nut, or it, and/or the spider gears must be very heavily modified to allow the now welded spider gears to pass its teeth without contact…

That still wouldn't do it - the inner gear is free-floating on the splines. You can't weld it since that would make hub service impossible. And if you shave off the spiders where they contact the inner gear/nut retainer then nothing holds the inner gear into the nut. You need a way to delete the inner gear and hold the nut from backing off and it can't be welded or you'll never service the wheel bearing ever again....... And then of course you are destroying the spider gear assembly which means there's no going back if you ever wanted to without buying all new reduction assemblies......

It's not going to be a simple weld job with a buzz box unless you just don't give a damn about your axles or servicing them. Anyone can be an idiot with a welder - you'll ruin more $$$ in parts than the ECO hub kit will cost you.

 

[BigMontana]

That still wouldn't do it - the inner gear is free-floating on the splines. You can't weld it since that would make hub service impossible. And if you shave off the spiders where they contact the inner gear/nut retainer then nothing holds the inner gear into the nut. You need a way to delete the inner gear and hold the nut from backing off and it can't be welded or you'll never service the wheel bearing ever again....... And then of course you are destroying the spider gear assembly which means there's no going back if you ever wanted to without buying all new reduction assemblies......

It's not going to be a simple weld job with a buzz box unless you just don't give a damn about your axles or servicing them. Anyone can be an idiot with a welder - you'll ruin more $$$ in parts than the ECO hub kit will cost you.

I've seen those "last modification" jobs outlast the entire vehicle. In fact lots of times they increase the reliability for the medium term future.

Also, I'm not sure how much you think replacement parts cost, but it seems like I could trash all four hubs and buy new ones for the same cost as the eco hub kit...and if I did that...guess what? Not gonna need eco hubs because I'm upgrading the axle/hub combo, practically everything on these vehicles is plug and play modular, and upgrade to the entire axle combo would hardly require fabrication.

 

[wheelspinner]

Exactly. Waste of time to even consider wrecking a bunch of parts by welding all over othem when a tested product is available to do it the right way. The hubs pay for themselves in ~3500 miles just in fuel savings. If you can't afford to do it the right way then these aren't the trucks for you and you'll fail on many more levels trying to cheap out like that. Those kinds of decisions are what lead to fatal accidents when you are working with 20k lb+ heavy equipment.

Here’s the deal. I already bought a set. I’m curious. So if I want to trash the parts I’m removing it’s my prerogative. I got plenty of money and I like the hub kit. I’m still curious.

 

[GeneralDisorder]

Here’s the deal. I already bought a set. I’m curious. So if I want to trash the parts I’m removing it’s my prerogative. I got plenty of money and I like the hub kit. I’m still curious.

Nothing wrong with being curious.

Having welded plenty of diffs as a young man with more 7018 and electricity than money for lockers I can tell you it will work till the welds break (throw some bolts or chunks of ready rod between the gear teeth and weld them in) - or maybe they won't break - the end result will be the same as the ECO hubs assuming you engineer something like the split ring in the kit to retain the wheel hub nut.

 

[Ronmar]

That still wouldn't do it - the inner gear is free-floating on the splines. You can't weld it since that would make hub service impossible. And if you shave off the spiders where they contact the inner gear/nut retainer then nothing holds the inner gear into the nut. You need a way to delete the inner gear and hold the nut from backing off and it can't be welded or you'll never service the wheel bearing ever again....... And then of course you are destroying the spider gear assembly which means there's no going back if you ever wanted to without buying all new reduction assemblies......

It's not going to be a simple weld job with a buzz box unless you just don't give a damn about your axles or servicing them. Anyone can be an idiot with a welder - you'll ruin more $$$ in parts than the ECO hub kit will cost you.

Exactly, lincoln locking it would require more problem solving/engineering. I looked into it as an option I could do myself way back when i was analizing deleting the hubs, but never solved all the issues and had to shelve the idea to finish building my house.

Mike produced the eco hubs before I ever got back to it, and i ordered one of his first sets A locking collar like he used would probably be the easiest way to retain the wheel nut...