Troubleshooting Transmission '47 pickup

[V8COOPMAN]

Originally Posted by PeteVS

Does your 3 speed have the 25 tooth cluster gear? If not, that might be a good option to get lower first and second gears.

Pete ..... Are you SURE about that 25-tooth cluster giving you LOWER trans gear ratios?

That 25-tooth cluster is one of the two available "Zephyr Gearsets" that was available back then. The other was, of course, the 26-tooth cluster. Both of these gearsets allowed the car to be WOUND-OUT in both 1st & 2nd gears, but both were notorious for being 'dogs' off the line which to me, indicates 'BIG dog trying to take-off UP a hill.

Stock old Ford 3-speeds normally have either 28-tooth (most common) clusters or 29-tooth clusters. The 28-tooth yields a 2.82 1st gear and a 1.604 2nd gear.

29-tooth clusters have a 3.114 1st gear and a 1.773 2nd gear.

Check-out this gear ratio chart BELOW provided by Mac VanPelt.

Coop

http://www.vanpeltsales.com/FH_web/f...gearratios.htm


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[GB SISSON]

You guys are making my day with all this knowledge. Many thanks!

[alanwoodieman]

I took the 29 tooth truck trans out of my 41 3/4 ton, it has a 3:25 9'' truck rear axle and you could not get up to speed with the 29 tooth. I used a 28 tooth trans gear set out of a 40 car and it works good. but as I said before do NOT back off in first or second gear it will eat up the rear thrust bearing/case

[GB SISSON]

Originally Posted by alanwoodieman

I took the 29 tooth truck trans out of my 41 3/4 ton, it has a 3:25 9'' truck rear axle and you could not get up to speed with the 29 tooth. I used a 28 tooth trans gear set out of a 40 car and it works good. but as I said before do NOT back off in first or second gear it will eat up the rear thrust bearing/case

So Alan, did you re-use the 41's case and install a new gearset or is the '41's original transmission still intact? Also, does the '41 3/4 ton have an open or enclosed driveline? It is all somewhat confusing, but sounds Like I should have the 29 tooth cluster if I rebuild my current transmission. I hope to call Mac VanPelt soon and ask what I should be chasing down. And I guess I really should wait til I get this thing pulled and inspected before I go off ordering anything.

[Tim Ayers]

Calling Mac would certainly be a good idea. I have not messed with big trucks and, without a picture or a manual, I just assumed they used the car/light truck stuff for engine and trans. but I could be wrong.

Your question about the '41 trans is good to clarify. If from a car, it will a side shift with closed drive. Not sure when Ford went to open drive in trucks, but the open drive, top loader transmissions are still fairly plentiful.

That said, if you find a nice mid-to late '39 top loader trans that has the improved synchros, it's not that difficult to convert it to open drive. I have all the pieces you would need for the conversion if you need them. Just send me a DM.

That said, it's important to note that all Ford/LZ clusters are a 1:1 ratio in third. The tooth counts being bantered about is referring to 1st gear.

Generally speaking:
-25/26 tooth LZ gears let you wind it out longer in first. 2nd gear is also wider than 28 or 29 gear sets.

-29 tooth cluster, usually found in trucks, rev up quickly, but were designed for hauling or towing. Usually mated with 4:11's. This would be the slowest, highest reviving set up, but allow a truck to be a used like a truck

-28 tooth cluster, mated to a 3.78 rear, is a nice balance of all the sets/ratios. First revs quicker than LZ gears and second is a little wider than the 29 tooth cluster.

This combo can be good choice for around town driving for under 65 mph. Most times, you can drive around in 2nd gear and still have good acceleration until shifting into third.

In my roadster, I often will roll up to a traffic light in 2nd and take off without dropping down into first. I have a 28 tooth/3.78 rear in this car. Albeit it's light and has a big CI flathead, but I've done this in other cars as well.

Add tall tires that I'd assume a 3/4 truck has, then the rear ratio drops down a bit from the 3.78.

[V8COOPMAN]

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Guys ...... It ain't hard at all to figure out what you have when you use the Mac VanPelt chart that I posted above in post #21, as well as in the link just BELOW in this post.


http://www.vanpeltsales.com/FH_web/f...gearratios.htm


Take ANY numerical ratio number that is listed on the chart and multiply it by your rear end ratio for an overall number that you can work with.

For instance GB, let's say that you now have the most-common gearset available which has the 28-tooth cluster. That cluster yields a 2.82 1st gear ratio. Now, let's assume that you currently have something like a 4.11 rear end ratio. Multiply the two (2.82 X 4.11) and you end-up with an 11.59 OVERALL ratio. You're obviously familiar with how the car climbs your hill with that overall ratio. NOW, you have a baseline ratio to experiment with different 1st gear ratios, as well as combining those with different rear end ratios.

And remember, IF you consider going with a T5, don't forget that you have synchronizers on ALL forward gears, plus you have an additional intermediate gear to get your RPMs in a "happy range" when you're cruising the island, and not to mention the available O/D for one of your occasional trips across the pond to the mainland. And those T5s really shift nicely.

One more link BELOW for all of the common T5s along with their individual gear ratios. Stick with the "GM" or "Ford" transmissions for reasonable availability purposes.


http://www.britishv8.org/Articles/Bo...T5-ID-Tags.htm


Coop

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[GB SISSON]

Originally Posted by V8COOPMAN

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Guys ...... It ain't hard at all to figure out what you have when you use the Mac VanPelt chart that I posted above in post #21, as well as in the link just BELOW in this post.


http://www.vanpeltsales.com/FH_web/f...gearratios.htm


Take ANY numerical ratio number that is listed on the chart and multiply it by your rear end ratio for an overall number that you can work with.

For instance GB, let's say that you now have the most-common gearset available which has the 28-tooth cluster. That cluster yields a 2.82 1st gear ratio. Now, let's assume that you currently have something like a 4.11 rear end ratio. Multiply the two (2.82 X 4.11) and you end-up with an 11.59 OVERALL ratio. You're obviously familiar with how the car climbs your hill with that overall ratio. NOW, you have a baseline ratio to experiment with different 1st gear ratios, as well as combining those with different rear end ratios.

And remember, IF you consider going with a T5, don't forget that you have synchronizers on ALL forward gears, plus you have an additional intermediate gear to get your RPMs in a "happy range" when you're cruising the island, and not to mention the available O/D for one of your occasional trips across the pond to the mainland. And those T5s really shift nicely.

One more link BELOW for all of the common T5s along with their individual gear ratios. Stick with the "GM" or "Ford" transmissions for reasonable availability purposes.


http://www.britishv8.org/Articles/Bo...T5-ID-Tags.htm


Coop

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Thanks Coop, that takes a lot of the guesswork out of the equation. Gotta juggle some cash I've been saving up for the 255 engine and most likely the least expensive way out is to re-gear/repair my lowly 3 speed. I'm sure I'd love the T-5 and who knows.... There may be an S-10 in the bushes here.....

[pistonbroke]

Hi Gary, Tim here, just a side note. I had the same symptoms in an old truck and found my pinion nut had come lose . Just another experience , Tim

[alanwoodieman]

Originally Posted by GB SISSON

So Alan, did you re-use the 41's case and install a new gearset or is the '41's original transmission still intact? Also, does the '41 3/4 ton have an open or enclosed driveline? It is all somewhat confusing, but sounds Like I should have the 29 tooth cluster if I rebuild my current transmission. I hope to call Mac VanPelt soon and ask what I should be chasing down. And I guess I really should wait til I get this thing pulled and inspected before I go off ordering anything.

I used the 41 top loader case, actually any top load 78 case will work. I have the complete 41 29 tooth truck gear set as a spare. 41 3/4 ton is an open drive shaft. does your trans have the parking brake drum on the rear of trans? if so you will need to find the top load trans out of a step van because it has the brake drum on trans output

[cas3]

Personally, if its gonna be a swap, I like the 4spd from the 80's f150's. 3 direct, and 4th is overdrive. No need for 5 gears I think.

[GB SISSON]

Tim, while driveshaft was out I found no wobble, play or looseness at the rear yoke. I was hoping that's what the noise was. Alan, the chassis a conventional 1947 1/2 ton pickup. Open driveline and parking brakes are cable to rear wheels. Skip, is this f-150 4 speed a tremec or related to the S-10 and use that same cast aluminum adapter as the T-5?

[cas3]

GB, I forget the correct name of the 150 trans. Someone will chime in on that. The model A guys like them because they are shorter than the T5, and the shifter comes straight out the top like the old Ford.

[V8COOPMAN]

Originally Posted by cas3

GB, I forget the correct name of the 150 trans. Someone will chime in on that.

The transmission you are looking for is an "RTS" out of an 84-87 Ford F150 2WD pickup with an inline 6 or small V8. Gear ratios and O/D ratios are limited compared with T5 selections.

[GB SISSON]

And really, an overdrive would be rarely used in the woodie. Our 'over town' car is my wife's 5 spd manual '96 subaru outback. Sometimes we forget there is a 5th gear as we use that OD so rarely if at all on the island. It's still a ways out before I can pull the trans and see what's going on in there so in the meantime I will continue my research.

[jimvette59]

GB I have one of the infamous 41 pichup trans. It is a 78 case for the v8 or the four cylinder. It is for sale. If you are interested you can get me at [email protected]. Jim T.

[38 coupe]

alanwoodieman, which 29 tooth gear set do you have? I suspect you have the 14 tooth main drive gear version that results in the even lower 3.52 first gear ratio. If so, that might be the perfect solution to GB's need for a low first gear.

Most 29 tooth gear sets are the 15 tooth main drive gear version with the 3.11 first gear, typically paired by Ford to a 3.54 rear axle ratio. However, the pre-war 3/4 ton trucks with the light duty three got the even lower ratio sets that are both not common and not (usually) desirable.

[GB SISSON]

Originally Posted by jimvette59

GB I have one of the infamous 41 pichup trans. It is a 78 case for the v8 or the four cylinder. It is for sale. If you are interested you can get me at [email protected]. Jim T.

Thank you Jim. We are off island (over town) on a 4 day road trip visiting relatives. I emailed you. We wiil be home tonight and tomorrow I will get back to my laptop. I was finally able to reset my password by email on phone. I much prefer doing all this barn stuff on my laptop. Do they make a large print edition of fordbarn?

[flatford8]

Gary, if you turn your phone sideways that print should be bigger. You can also put your fingers together, touch the screen and spread your fingers while contacting the screen. I agree, the laptop is easier…….Mark

[38 coupe]

Originally Posted by GB SISSON

Do they make a large print edition of fordbarn?

Kinda. Hold down the control key on your keyboard and hit the plus key until you can read the words. That zooms the screen size of the web page which can help or cause problems.

[GB SISSON]

Thanks guys, need all the help I can get. Just texted a guy in a town we are driving through next that it doesn’t look like my wife and I will be stopping to look at the 40 ford pickup he has listed. I have a lot more vision about what stuff will look like ‘after’ than she does…. Heck, I was only gonna just take a quick look. Sheesh.