Just rebuilt transmission

[delco1946]

Morning all, I just had my 1955 fordomatic rebuilt and have about 100 miles on it. It has very firm shifts now which I don’t like but it seems(?) to be getting softer. They reused the original plates which were in good shape and rebuilt the torque converter. They recommended tracter oil (5 or 10 weight) which seemed good - they seemed to know their stuff and didn’t recommend type f ( I’m not asking about oil so let’s not side tangent into that ). I am curious as to when others’ shift into 3rd? It used to shift into 3rd around 25 mph, rarely downshifted into 1st. Now it won’t shift into 3rd until 40 to 45 mph if I’m even feathering the gas. Did I just get used to an old sickly transmission? Is this a better range? It’s certainly louder and will result in worse miles due to higher rpms but I’d prolly get better acceleration/control. When Does yours shift? Also, I’m a little concerned about what feels like a hesitation/slip when starting from a stop light ( in 2nd). It takes a couple seconds for it to feel as responsive as it used to unless you gas it and force it to down shift. Is this a band adjustment? I go back in a couple hundred miles for a free check/ adjustment so I want to know what to ask for.

[Hot Rod Reverend]

the old fordos always started in 2nd, never in 1st unless you floored it from a stand still. The best thing to begin with on adjustments is to be sure you have a baseline for linkage. The shop manual will indicate how to line up the holes at the carb linkage assembly on the intake manifold. Once lined up (with a dowel rod or sometimes the right diameter screwdriver shaft) you can then make an initial setting on your kickdown linkage. This rod that goes to the springloaded arm on the side of your transmission is length specific for sure. Adjustments to make the rod longer will mean you shift earlier. Adjustments to make the rod shorter means you shift later. The springloaded lever basically manages the load to the gears...

40-45 mph upshift to 3rd does seem a little late unless you are really flooring it (and of course you say you are feathering it and all). As I recall back when I ran a fordo each day, it was basically the 25-35 range that I had upshifts to 3rd and that was what I liked anyway.


did the shop put the transmission back in for you or did you do that yourself? I would think that the adjustment on the linkage is the place to begin if they rebuilt the transmission correctly.

the firmer shifts may be because of the fluid they recommended, not sure about that and don't want to get into the trans fluid debate, but of course.... the fluid you use makes a dramatic difference because that fluid controls the friction between plates.

[delco1946]

The shop did everything, and considering the price I paid I will be asking them to be doing the adjustments. I’m just trying to get an idea of what other fordomatics do in case I’m biased from my old transmission. I know the start in second, it’s still does that but does feel like it takes a couple seconds to solidly engage ( which is not enjoyable).

[Daves55Sedan]

Tractor oil, 5 or 10W ???
Fordomatics should use Merc/Dexron automatic transmission fluid. Check fluid level at the dipstick while engine is RUNNING and gear shift lever is in neutral.
I completely agree that the old brass clutch plates can be re-used if still in good condition. They will probably long outlast the composite discs found in modern rebuild kits.
Transmission should shift from intermediate into 3rd at around 27mph if passing gear link is adjusted properly AND there are no fluid pressure problems.
The 1956 Fordomatic shop manual (not the car shop manual) gives excellent detail in adjusting the passing gear link. This adjustment is critical in obtaining proper shifting.
Once that adjustment has been corrected, the delay in downshifting at stop signs will disappear also.

[bfdinardo]

Delco,
The adjustment procedure pictures can be found in the thread I started here, https://www.fordbarn.com/forum/showthread.php?t=267376. I'm actually installing a tachometer for this exact reason to see at what RPM my fordomatic is shifting from 2nd to 3rd but based on feel I'd say i'm close to the 25mph mark. As you can read from my thread, when the linkage was sticking I was experiencing exactly what you are right now, late (35-40mph) and harder shifts.

[delco1946]

Sponsored Links (Register now to hide all advertisements)

Yup they said no to type F and recommended and used tractor oil 5 or 10 wt. Not sure how invasive I should be with them, I left them my manual but they didn’t look at it for making adjustments. it’s not like they’re rebuilding a bunch of fordomatics that often but On the flip side considering they’ve rebuilt thousands of transmissions they probably know a thing or two.

[delco1946]

Ugh now I’m wondering if I should have been more vocal vs deferring to their experience. I hate being in this position :/

[KULTULZ]

... whew ...

How many experienced re-builders will still be around with fifties trans tech knowledge? It would have to be a specialty shop I would think.

As for motor oil, that was thirties/forties tech.

They re-used the clutch plates. Did they charge you for a complete overhaul set?

[delco1946]

Well he was certainly old enough i'd say, and transmissions are their bread and butter. Not sure what you mean by overhaul set but they charged labor for a rebuild ( took it apart piece by piece due due the X cross-member underneath). The alternative was pulling the engine out to the tranny out in one piece.

They rebuilt the torque converter, put new seals, some smaller parts (springs?), etc. They said it was in pretty good shape generally, but replaced the rear band which was chewed up/damaged and had to fashion a new one due to parts availability. (I also gave them a MACs catalog just in case but i doubt they saw that either *rolls eyes*).

I don't have the bill in front of me regarding specifics.

[delco1946]

and I guess if folks really think that they made a mistake by using "tractor oil" versus dexron/mercron, i could always have it changed and bring a new pan with a drain to simplify this in the future. It sounded like they considered the two pretty similar or at least both work well.

[KULTULZ]

Originally Posted by delco1946

...and I guess if folks really think that they made a mistake by using "tractor oil" versus dexron/mercron, i could always have it changed and bring a new pan with a drain to simplify this in the future. It sounded like they considered the two pretty similar or at least both work well.

I have no idea of why the trans fill. Even TYPE A was called for in this time period (DEXRON III is the superscession)

If you decide to use DEXRON, you will have to fully drain the convertor and main case and then partially fill (until convertor fills) and then go to a flush procedure. What comes out has to be entirely clean ATF.

What warranty did they give you?

Hate to hear crap like this.

[delco1946]

12 month warranty.

[rotorwrench]

The throttle control valve that accompanies the gear selector is what controls the pressure in the transmission. The Borg Warner single range and early dual range transmission designs runs entirely from fluid pressure. The gear selector is just that. The TV rod is everything else. It's better if a person uses a pressure gauge to adjust it by the book but it can be adjusted by trial and error if a person doesn't get carried away. Mark where you started and start adjusting it. A stall test to check the band for slippage is not a bad idea either but the pressure tests will get it working like it should.

Ford Type F oil was developed to insure positive shifts in the Ford/Borg Warner design transmissions with metal on metal clutch plates so they wouldn't slip when the pressure is lowered. It's a balance between a positive but livable shift and a harsh shift. The Type F was developed in the later 60s when the use a whale oil was no longer in vogue. Type A GM fluid from the early 1950s is not available in its original form (no whale oil). Modern Dexron/Mercon fluid is designed to work with clutch packs that have steels with composite plates like all modern transmissions have. The modern fluids have conditioners and other additives that type F doesn't.

If you use Dexron/Mercon just make sure the that you don't let the clutch packs slip for any length of time if they are still bronze & steel type plates or it will ruin them quickly.

Some folks say don't run type F! Drag racers have been running it for years in all sorts of different transmissions to get more positive shifts but that's what you want when you drag race.

[delco1946]

Rotorwrench and others- any idea then if old fashioned tractor ( does that mean transmission or hydraulic?)fluid is ok then? I doubt my plates are slipping currently as I feel firm shifts. I’m ready to have a heart attack. Also makes me wish I had a drain plug.

How on earth do I have any control of the clutch packs slipping if I use dextron for any length of time?? They’re the original plates.

[Daves55Sedan]

The dipstick tube connection to the pan IS your drain plug. The Mercury medium case Fordomatics did have a drain plug besides the dipstick tube, located near bottom of the front of the pan, but the medium case pan is not interchangeable with the small-case Fordomatic pan.
If you decide to add a drain plug, be careful to locate it such that it will not interfere with anything just above the pan. It is very close quarters an many spots.
I suggest using a half-coupling and pipe-plug. After drilling the proper size hole, have a pro continuously weld the half-coupling in place and be sure to check for leaks before installing.

[delco1946]

I’m guessing it’s cheaper to buy a new pan with a drain than to pay for a wielder. I’ll do some sleuthing to see if that’s available. Sucking up fluid thru a dipstick is not what I consider to be a drain.

Macs has a couple options but not sure if they’re compatible. I probably just need to go sit and forget about this for a while before I get anymore frustrated by this whole process.

[dmsfrr]

Originally Posted by delco1946

... I’ll do some sleuthing to see if that’s available. Sucking up fluid thru a dipstick is not what I consider to be a drain. ...

Unscrew the large nut holding the dipstick tube to the pan, that will drain most of it.
Is there a drain plug on the front side of the torque converter? It might be accessible by removing the lower front cover.

[rotorwrench]

It probably should have ATF in there. They used to use light oil back in the 40s & 50s as a replacement oil for the old GM type 1 and type A. They added the red dye so they could tell if it was a transmission leak or an engine leak.

When I mention a person shouldn't let it slip, I'm just stating that don't drive it if it starts to slip. Do some checks on it to see why it's slipping before driving it again. You don't seem to be having that problem.

What you describe is not slippage. It sounds like the pressure is a bit high if the shift is harsh but there might be something else going on in there with the high shift speed.

Your governor controls the shift speed. I just wonder if there is a leak anywhere inside there that could be causing a late shift. The transfer tubes in the governor set up can leak if they weren't installed correctly. The seal rings can leak too. They should shift into high around 25 mph under normal throttle settings.

[KULTULZ]

Maybe go by the shop and ask exactly what fluid they used as you will need to know next time it needs service. Once their lubricant usage is known, a better understanding of what, how and why.

Did they give you an estimate for in-chassis overhaul and/or bench overhaul (remove engine-trans)?

[Hot Rod Reverend]

Originally Posted by bfdinardo

Delco,
The adjustment procedure pictures can be found in the thread I started here, https://www.fordbarn.com/forum/showthread.php?t=267376. I'm actually installing a tachometer for this exact reason to see at what RPM my fordomatic is shifting from 2nd to 3rd but based on feel I'd say i'm close to the 25mph mark. As you can read from my thread, when the linkage was sticking I was experiencing exactly what you are right now, late (35-40mph) and harder shifts.

Use Brian’s link to make initial adjustments. Start with a baseline and go from there...it’s all conjecture until you get the rod adjusted correctly per factory spec.