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PT81Jan last won the day on January 31 2016

PT81Jan had the most liked content!

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About PT81Jan

  • Rank
    Advanced Member
  • Birthday 04/12/1971

Profile Information

  • Gender
  • Location
    Germany; Friedrichshafen
  • Interests
    Especially Bikes and Cars of the 30s and 40s with Flathead engines (others are also welcome!)
  • My Project Cars
    - 1939 Plymouth PT81 Pickup Truck<br />
    - (1942 HD-WLA)

Contact Methods

  • Biography
    born 1971, married, children, 1st occupation: patternmaker, 2nd occupation: engineering technician
  • Occupation
    Designer / Engine Development


  • Location
  • Interests
    Still love my PT81

Recent Profile Visitors

314 profile views
  1. Thank yo Merle, I only know that there are 10 bolt and 11 bolt carriers, but I do not know the difference up to now... Thanks DJ, first paragraph: ring and pionion of what kind of vehicle to what kind of vehicle's rear? (passenger /truck) fourth paragraph: veeeerrry interesting !! Hahaha, cool attitude. That is what I wanted to hear. Would be nice to hear of the result ! Thanks Desotodave, I have read about a probable necessity to change the side gears in some reports. Where does the need come frome ? Lack of clearance between gears? The altered ratio should not be a problem !? (thats at least the technical part of my brain makes me thinking...) Thank you Jeffsunzeri, Entire carrier of a car into a 47 Dodge truck? To all: your feedback contains more info than I did expect. To be honest, I was thinking that swap might be too easy to be true. Most reports are of complete rear end swaps or to put in an overdrive or an other transmission in combination with a more modern rear end. Every single info regarding my question is a great help ! Thank you again, Jan
  2. Has anyone already made such a swap (passenger car ring and pinion into truck rear end carrier) ? Any input on this ? Experts knowledge is appreciated.
  3. I have been in an intensive information exchange with another forum member the past weeks regarding a never ending subject to our trucks: how to alter the rear end to get a better road performance. We did some research, have read many reports in the forum here and many other sources. We both ave a 1939 Plymouth PT81 truck. We plan to change the ratio from 4.1 to 3.73. What we know we could do: 1st: a swap to another rear end out of another vehicle like Jeep Cherokee, Ford Explorer or something else (not what we prefer) 2nd: a swap of the axle carrier assembly (11 bolt, 10 spline shafts) out of a mopar passenger car, years 37 - 53 -> passenger gear carrier to truck axle housing (didn't find one up to now) 3rd: exchange of the truck's 4.1 ring and pinion to 3.73 truck ring and pinion (impossible to find) Long story short: What we would like to know is: Does anyone know, if ring and pinions out of passenger cars fit to the truck's ring and pinion carrier? To be more precise: 3.73 ring and pinion out of any mopar passenger car to the 1939 Plymouth truck rear end carrier ? Thank you much ! Rear_Axle_Fundamentals.pdf
  4. Draft tube

    Thank you for that perfect description - made me aware that I was misinterpreting the original question... below the oil pan, not into the oil pan. Sorry
  5. Draft tube

    Really? This is the crankcase ventilation outlet and if directly lead back into the oil pan the ventilation would no work !? The tube on my motor is a bit longer btw, but leads to the environment, too. There is no connecting piece for a hose at the pan. Just my thoughts... Curious if there exists a solution that leads separated oil back to the pan.
  6. Running without inner/outer fenders

    There has been a similar topic in the truck site - hope that helps !? http://p15-d24.com/topic/43933-where-under-hood-battery-location/
  7. Wish you good vacation! Would be nice to exchange information sometime later.
  8. Whose Truck Got A Workout?

    Snappy ? Thought this was an early BMW that had to be towed ...LOL
  9. I also can imagine that other axles which indeed fits are not listet, because they do not fit the original application. Trucks might need some stronger gears for example. But I am not too worried to use an axle out of a passenger car in my truck (if I find one) since I do not plan to carry a heavy rock around the area...
  10. Hey Jeff, have seen a rear axle for sale near to my home today (unfortunately I have been the second guy that was interesting in...). It has been out of a 1955/56 DeSoto. 3.73 ratio. Every relevant dimension seem to be the same as that of our PT81 axle. 61" wide, 5 x 4.5" wheel bolt pattern, drum brake and also the shape of the axle housing is pretty similar (for the original look). Also the axle drive pinion flange seems to be the same type (dont't know the exact dimensions). Maybe an alternative to the difficult to find 3.73 ring and pinion or other solutions ?
  11. rear diff cast numbers chart

    Is that number out of your PT81 ? If so, I am surprised. My PT81 rear differential cast part No. is 663473-4
  12. Equipment: I also have the original 3 speed behind a 218, 4.11 gears and 15" tires. Not really nice to drive in traffic at a speed limit of 100 km/h (about 63 mls) ... Gears of any MOPAR: Depending on the manufacturer there are different encodes for the same ring and pinions. If I knew all the part-No.`s of the gears that fits to my rear, it would be able to expand my search to get the correct ones. The risk to get parts that do not fit is too high for me, since I have to pay nearly the same price for shipping and taxes as that of the parts. By the way: I found some fairly used Jeep Cherokee rear axles here -> about 1200 €. One good as new last week -> 2300 € ... that hurts ...
  13. Hey Jeff I was asking a similar question regarding a PT 81 diff swap here some time ago. Not to destroy your expectations: although I am almost daily searching for one in the www. I didn´t find one up to now. I also was asking several mopar parts providers. No 3.73 ... If there is an information that helps you, this was the topic/content: http://p15-d24.com/topic/40346-plymouth-truck-ring-pinion-gear-for-changing-gear-ratio/?tab=comments#comment-428083 An alternative for me is still the Jeep Cherokee rear axle, but my first choice is the Plymouth 3.73. Would be nice, if we can benefit from our both information that we got / get to find a 3.73 diff. Enclosed some information that I have (klick to enlarge): If you have more luck to find one, please find two
  14. Ah, and regarding your neat differential gasket - don 't let our suggestions stop you to install it. Test it and let us know your experience
  15. I am sorry if I have to disappoint you. I am afraid that you have to use a new gasket all the time, if you have to remove the pan. The cork is compressed due to the installation, so I doubt it would give a good sealing a second time anyway. I bought a big cork plate and cut out some gaskets more for that reason, so it is not too much effort and costs.