Transmission Wear and Odors

[TeeScott]

Gents,
Here are a few pics from recent work to inspect/change the filter and fluid in the 727 trans of my '73 340 auto Rally Challenger. The filter was about 1/2 covered with very small bits of metal similar to what is visible in the bottom of the pan.
Car has 92K original miles w what I believe to be the original engine(block and head serial numbers are correct for the year) and transmisson. (This might be the first time the pan has been removed?) I've owned the car for ~2-1/2 years and the engine runs clean(uses nearly no oil btwn. changes), plugs run a nice tan, & pulls well; the trans shifts fine but is sometimes a little slow to engage into gear when shifting out of park/neutral. It might also slip slightly under hard accel. in top gear, but car will lay 2 healthy black marks from a standstill with no slippage.
So,...
(1) should I be concerned about this level of metal contamination since the trans. works O.K.? I expect this is clutch wear but I have very little experience in working on/troubleshooting trans. problems.
(2) I think the trans is also emitting a smell like lightly burning rubber/oil at higher rpms or just after accelerating hard. Is this a routine type of odor for a well used/worn 50-year old trans? Or could this be a small amount of blow-by from the engine? (engine has a Stock-type PCV connected on the driver's side valve cover; the pass. side cover just has a 3" dia. pleated filter installed for venting.)
I have been troubleshooting this odor since shortly after buying the car. Have gone through all the wiring & eliminated various other possible sources. I am using a 600 cfm edelbrock carb that I got from a friend that was lightly used and seems to work fine but I haven't tried swapping it out to see if it is running too rich for some reason. Any ideas/advice is appreciated.

TeeScott

 

[Xcudame]

Regarding the transmission, looks like normal clutch material as you guessed. Hopefully you adjusted the front (outside the case) and rear (inside the pan) bands while performing your filter/fluid change. That will help with the slipping.

Depending on the age of the PCV valve, it could be plugged up. A soak in gasoline usually cleans it up pretty good if it's not too coked up. That could be causing your "smell".

 

[540HemiCuda]

Frankly, lots to unpack here................

First, some amount of metal in the filter is normal. When there is a magnet in the pan, they often look like a furry animal even when everything is normal.
Second, if the fluid is getting dark and has a burnt smell, those a bad signs.
Third, the seals in the high speed clutch are prone to get hard and not seal well as they age or have experienced excess heat. Some good trans medic product MIGHT soften and swell them enough to give them some extra life IF they are not already too far gone and the clutches are still in good condition. SeaFoam TransTune seems to get good reviews. But, it is likely just a matter of time before the seals and clutches have to be changed.
Fourth; our torque converters are prone to drain back into the pan when parked. Interestingly, the front pump is not actuated in park, so only when the shifter is moved out of park does the converter get charged. I would just start the car in neutral. There is a kit readily available that reduces or eliminates the converter drain back.
Fifth, adjusting the bands will not do anything for 3rd gear slipping. High gear is clutch applied. But, while low/reverse band doesn't usually need as much attention as the second gear band, adjusting it while you have the pan off is a good idea since is it only accessible then. And you don't have to be exact. Ballpark is just fine. Second gear band adjustment (the one on the outside of the case) is a bit more critical as it affects the 2-3 shift timing to some extent since it affects how quick the band applies and releases.
Lastly, the line pressure is easy to adjust. A little more pressure MIGHT help hold the 3rd gear clutches better. I would certainly try that while you have the pan off as the adjustment is accessible then.

 

[Challenger RTA]

Ok I'm not a trans type of guy. Very good info above. I had a number of experiences with them. My brother had a problem with a Caravan. late 80', I have 2 dodge Dakota's. No! wait 3 now but any how. Well 4 actually the fist one is gone. Bad frame broke my hart. Actually the the second one I bought (2010?) just for the use of the snow plow (White). Put a transmission in. The yard where I bought it from said they would only guarantee it if I put a new radiator in. Did so. A few months later I was acting up. Call the yard and they said change the filter and fluid and save receipts. We will give your money back plus. If it doesn't fix it. Did so!

At that time same I also bought another Dakota ( black) the seller said the transmission was bad. My son was helping me. So for a fitter $6 change and fluid we did both. The plow truck was shifting a lot better but would act up now and them for a short time. The third truck (Black) was moving but just not quite right. It would slip.

Contacted the yard again and they said they will extend the warranty. But they said drive it. And change the filter again. Did so in a few hundred miles it got a little better.

I'm not a snake oil person but this fixed both trucks and my brothers Caravan years back.
I was talking to my brother about it. He said it fix his Caravan until the day he got rid of it. Years.

Both Dakotas run to this day with no Transmission problem.

This is what fixed it. Sea Foam Trans Tune. So before I would go wrenching I would do a filter a filter change. As The yard said. " The transmissions gum and varnish up from sitting."

Here again. My son was having trouble with his SUV. 130 mi. Told him change the filter and use trans tune. 6mo latter not a problem!

 

[Challenger RTA]

Here are a few pics from recent work to inspect/change the filter

If you ask me that is Varnish buildup. If it's not getting fluid it will smell from overheating. Also check linkage.

 

[540HemiCuda]

Just to be clear: I don't normally recommend any kind of repair in a bottle. But, it is quite common for the clutch pack seals to harden for the reasons I mentioned. And SOMETIMES the solvents in the bottled repairs will soften them enough to show improvement. SOMETIMES.

And the possibility of the seals being softened is the ONLY reason I mentioned it.

.

 

[TeeScott]

Gents, as usual, I appreciate all the feedback/advice.
1) Trans. health: the only reason I had the local shop (working on other stuff) to pull the rans pan was because it was slightly leaking. We Did change the filter, but since the shop was not a transmission place, nothing else was checked/adjusted. So, I will be planning to have it looked at by a local trans. shop and will keep all your recommendations provided above in mind.
2) Trans smells: This issue continues to bewilder me since it is NOT like any type of engine blow-by/oily smell I have dealt with on some high mileage/worn engines in the past. That experience, coupled to the fact that none of the valve cover vents or PCV tubing shows any signs of any excess oily residue AND there are zero vapors visible if I remove the vent cap from the pass. valve cover when running the engine at a few thousand RPMs in park...., keeps steering me back to the transmission as a source.) The smell is a "sweeter" (for lack of a better adjective), than engine blow-by or gas fumes, so I am still thinking it is trans. fluid. Odor is most prevalent after hard acceleration or after running at high RPMs for a while....Then it mostly dissipates when cruising normally. Any how...

THX again.
TeeScott

 

[Challenger RTA]

The smell is a "sweeter"

Anti freeze. Trans cooler in the radiator bad?

 

[540HemiCuda]

Sounds like something is either getting hotter than normal or leaking when you push it hard.

.

 

[Xcudame]

Power steering pump?

By the way, I have an 89 Dodge Cummins, shifter like crap and probably in need of a rebuild, but I put a new filter and adjusted the bands and it's running pretty damn good with 260,000+ miles on it!!

One thing I like to do on any early 727 trans is add a deep pan from the 518/46rh transmission and filter extension. more fluid is a good thing!