anyone here drive a NP435 with GOOD synchros?

[LCAM-01XA]

If yes, how smooth does she shift? For comparison purposes I present my T19, where you clutch halfway in and put a slight pressure on the shifter and she just slides out of whatever gear she's in and right into the next one, smooth as can be. On the other hand my NP435 appears to do just the opposite:

1-2 shift feels like three "bumps": a good one while pulling her out of 1st, another as she goes into what would be neutral if I let go of the stick, and she "catches" once again as she goes into 2nd.
2-3 is actually pretty decent, every once in a while there's slight "catch" as she enters 3rd.
3-4 also feels bumpy, but not anywhere near as bad as the 1-2 shift, just a single bump as she enters 4th.

Additionally, the whole revv her to the moon then shift simply doesn't happen with this one, I can do a 2-3 at over 3000 but 1-2 and 3-4 are pretty much maxed out at 2500rpms, any higher than that in the lower gear and she will fight me going into the higher gear and requires rev-matching with the throttle (as opposed to the T19 where by the time the engine speed drops on its own past the "float" point she's already in the next gear). Still goes in gear fine tho, never misses, I just gotta be aware of her quirks and work around them.

So I'm pretty sure my 2nd and 4th gear synchros are about done, 2nd worse than 4th. Question is, if I tear her apart and give her new synchros, how smooth will she get? Can she ever match the T19 which dang near shifts herself? Or will it be just a minor improvement over her current behavior? I'm trying to figure out if it's even worth it to pull and rebuild this thing, or just run it as is while I look for a creeper T19 to rebuild for butter-smooth action like my close-ratio T19. Personally I don't much care one way or the other, but I got a teenage girl who wants to (and should) be able to drive the truck as needed, and she just doesn't feel very comfortable with the NP435 as it is now...

Thanks!

 

[73IDI]

Ive got 2 trucks with 435's and had a third (as my first vehicle) their all 70's models (dont know If that matters) and they all shift smooth in 2-4 if you use the clutch but 1-2 is always a little choppy not like rough but you can feel it come out of first I think this is because first is not synchronized anyway and is so low its basically useless unless you have a load or are on a super steap incline and for parking of course but 2-4 should be plenty smooth not just falling in and out of gear but smooth and plenty easy for a beginner hope that makea some since sorry if I rambled on

sent from my phone so my spelling and grammer most likely suffer more than usual

 

[chris142]

What oil do you have in the 435? A regular gl4 or 5 gear oil can damage the soft parts in that trans. The proper oil is a sae 90 gl1 oil or sae50 motor oil ,

 

[LCAM-01XA]

73IDI, I suspected some of the choppiness of the 1-2 shift, especially pulling out of 1st, is due to the the non-sync creeper ratio - that shouldn't be a big deal as long as going in 2nd and then 2-3 and 3-4 are fairly smooth. Big loads and inclines (but mostly big loads) is why I got this transmission, the 4:1 T19 while very pleasant to shift simply wasn't doing too great in that department. The NP435 in question is also a 70s unit like yours, so your experience is very valid for it. And girl is not really a beginner, she can float a 10-speed quite well actually, and she was very happy with the T19, it's just the choppy way the NP435 shifts really bugs her - you know when something about how a vehicle runs seems unnatural you always tend to think about it which distracts your from other stuff you could be paying attention to, I wanna have this thing almost to the point where it about drives itself so she can not worry about what she may be doing to the trans and instead focus more on the stupid people zooming around her at mach 3.

Chris142, it's regular axle gear oil in there right now, that's all I had at the time. But there are only a few hundred miles on that transmission since it was installed, and it shifted that way right from the beginning. So I'm quite confident that I didn't do any damage to her, and all the current issues can be contributed to her previous live - it's a junkyard transmission that came out of a 70s farm truck, I doubt it lead an easy life there and it's anyone's guess what oil was in her till recently. Basically I pulled the shifter and looked inside, drained the oil and watched it come out clean, so I figured nothing catastrophic was going on in there and so I bought her. Stuck her in the truck to see what she actually does, filled her up with whatever heavy oil happened to be around, and drove her. If she shifted good oil was to be changed to the proper kind, if she didn't I'm running the GL5 till she comes out for rebuild. But there was a reasonable chance she could be in decent condition, I wanted to know where she stands before I start buying stuff.

 

[chris142]

Its prolly just worn out.that and the farmer used gl5 in it too which helped wear the soft parts out. Would not hurt to try some sae50 just for giggles

 

[oregon96psd]

Could it be that the detents in your t19 are shot, where your np435 still has good ones? That might explain the couple clicks when shifting. I know my t19 basically doesnt have any, no hold pressure at all (and actually I dont know that they really should, Ive been paying attention to them at junkyards and none ive felt do), but my zf definately does and you can feel them when shifting.

On edit, does anyone know if a t19 shifter should center itself under 3rd and 4th when in neutral, instead of just flopping around wherever?

 

[LCAM-01XA]

Chris142, aye, that's what I'm thinking, high miles and wrong oil probably. I may try the SAE 50 oil soon, I kinda wanna see how things look like in the bottom end as well, for whih I'll need to pull the PTO over.

OregonPSD, the T19 detents are fine, by sliding in and out of gear I mean the shifter moves nice and smooth, like a newer 5-speed transmission. As opposed to having to put some effort to get her out of one gear and into the other, as is the case with the NP435. The T19 is in excellent shape overall, very pleasant to drive. By the way both my T19 and NP435 feel exactly the same when "dry-shifting" them with the engine stopped, one is not choppier or smoother than the other then, it only shows when engine is running.

Also, yes, your T19 should center between 3 and 4 in neutral, well kinda - there's still a lot of looseness in there, but you do have to overcome a spring when you pull it to the left before you can put it into 1st or 2nd. Pretty much the same as shifting in reverse, only not quite as pronounced. The NP435 on the other hand does not have the spring-loaded stop on the forward gears, when in neutral the stick is allowed to flop sideways freely between the 1-2 and 3-4 forks, the only time you're pushing against a spring is when moving to the right before engaging reverse. I have a T19 shift tower laying around, here's a picture of what's inside it under the shifter:

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The middle shift rail, with the two verical roll pins, is your 3-4 rail. The left rail, with its slot blocked by the big horizontal cylinder-like pin with dirt on it, is the reverse rail - cylindrical pin is spring-loaded, as you move shifter to the right its tail pushes pin to the left and into the rail which eventually allows shifter tail to engage rail slot. The right rail, with its slot blocked by the smaller horizontal round-tip pin, is the 1-2 rail - the round-tip pin is also spring-loaded, as you move shifter to the left its tail pushes pin to the right and into the rail which eventually allows shifter tail to engage rail slot. At in neutral shifter tail rests between these two horizontal pins, and thus can only engage the 3-4 rail when moved fore-aft. The NP435 lacks the horizontal pin in the 1-2 rail, thus while in neutral the shifter tail could be in either the 1-2 or the 3-4 rail, or between them thus engaged in both at the same time, all depending on where you let go of the shifter.

One thing to consider is that the slop in the T19 shifter in neutral is often caused more by the shifter twisting inside the tower, than by it swinging left-right between the rail pins - this is because the T19 only uses one shifter slot & housing pin to indexes the shifter to the tower, and said indexing pin is not exactly pressed in the housing but instead kinda just slides in it - combine worn slot in the shifter with oblonged housing hole for the pin and possibly worn pin too, and the shifter is now allowed to twist around a vertical axis quite a bit. And with the shifter having the funky shape it does, any vertical-axis twist of the shifter translates into sideways motion at the knob, thus giving you the impression the shifter is not centering in the 3-4 rail at rest. Actually you will experience nearly the same amount of slop even when shifter is in gear, especially in 3rd and 4th - again shifter tail is engaged in the correct rail slot, only the shifter is still twisting in the housing slightly. The NP435 on the other hand has two shifter indexing slots and their pins are also pressed into the housing making for a much tighter joint, however as mentioned the NP435 does not center in the 3-4 rail at rest so you still end up with lots of sideways slop at the knob. Once in gear the NP435 shifter is not quite as sloppy as the T19 tho, courtesy of the double indexing slots that allow for very little rotation inside the tower.

 

[73IDI]

LCAM-01XA, basically I think your unit maybe a little wore out cause like you say 2-3 and 3-4 should be plenty smooth for some home who is experienced or a beginner as far as oil goes all mine have always had like 80w-90 (I believe thats the weight haven't used any for awhile) gear oil and not had any issues but I don't drive my 435's at interstate speeds (mainly cause the trucks are all 4:10 rear end so can't really go that fast) so maybe thats a factor for me

sent from my phone so my spelling and grammer most likely suffer more than usual

 

[ToughOldFord]

The NP435 and T18 have a "granny gear" first, you do not use it unless you are moving a serious load. Start in second and drive it like you normally would. This is not a shortcut, it is in the owners manual of your truck. The shifter would have been more appropriately marked "L-1-2-3" than the 1 through 4 it has on it.

Even if your transmission was new and not wore out you would not get a smooth 1-2 shift out of a NP435 (or T18).

 

[ToughOldFord]

Oh, and to answer your question, yes, with the transmission and clutch working properly the NP will shift as smoothly as the T19.

 

[Greg5OH]

man, id love a granny gear. both forward and reverse.

 

[riotwarrior]

Yeas ago me father had his NP435 rebuilt all new synchro and bearings, shifted great, I recall it having a slightly notchy feeling though but worked great!

 

[Slade]

The older 435's I've run just needed to be shifted slowly and then they shifted nice and smooth.

 

[KyleQ]

I have one in my 351W powered Early Bronco - shifts great. Although I did manage this once though...

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[freebird01]

I have one in my 351W powered Early Bronco - shifts great. Although I did manage this once though...

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i got another one i can sell ya.... its the correct 2wd np435 for the EB swap with the short tail shaft and square bolt pattern....