So wanted to ask a question I have a 53 dodge meadowbrook with a 3.9 rearend and also have a 54 meadowbrook with a 4.1 rearend and wanted to know could I swap the 3 9 for 4.1 and will it make a difference and will it work any information on it would be greatly appreciated also if someone could help in what the dimensions are for my 53 stock radiator is H x L x T as well as what row 2,3,4, I should get please and thank you
About the only difference you may notice between the 3:90 rear gear and the 4:10 rear gear is a few more RPMs on the highway with the 4:10 gear. As far as the radiator, do you still have the flathead 6, are you keeping it, and has any performance stuff been added? Those flat head 6 motors usually didn't have over heating problems unless the distribution tube in the block was bad, or there was a coolant leaking from something. I believe all the cars used the same radiator, but the trucks may have had taller radiators. The early radiators (pre-1930s) were not pressurized. Somewhere around WWII Chrysler added 7 lbs of pressure to the system, then later upped the pressure again in the 50s. Are you replacing your radiator with a new one? The lower radiator hose set up will require a radiator specifically for the flathead, I believe.
My choice, if the rear works okay, leave it. My first hand me down car was a 53 with a six and Gyromatic.
Gene thank you and the only reason I want to change it out is I bought the 54 for parts and the rear end looks good the 53 my daily the leaf springs have broken brackets and there is a oil leaking from the yoke i belive where the drive line connects and as for the radiator part the 53 had this aftermarket one put in and whoever did it did a poor job they cut out a big chunk of the radiator area to make it fit as you can see in the picture provided i do have the L6 Flathead still in it no performance has or will be added just wanted to find the measurements to see if I can find and one put one in as I'm using the front clip to the 53
Thank you tow truck Tom and the only reason I asked is the leaf springs are pretty bad and leaking oil so just want to see if the one I git for parts of the 54 for my daily 53 would work
Then There it is, the IF. Soo we need to upgrade to a '54 since we have one. Of course you may want to get the speedo calibrated. Else wise you'll be slower than the rest of this racecar world
A good old hack job on the core support there! If what is there fits and works you could maybe fix it up some with say box section (or a folded profile) to replace the lost strength. The originality is shot to pieces already and if you don't have the cutout pieces etc etc.. Chris
The difference between the two ratios is only about 5% (4.1-3.9 / 3.9 = 5.13%). So your rpm will increase by about 5% with the 4.1 vs the old 3.9 rearend. If you cruise at say 2500 rpm with the 3.9, the 4.1 will take 2628 rpm for the same speed.
Does the parts car have a good radiator support? If it does, I would swap it ***uming it is the same as yours.
The above two replies are both worth looking into. I would really want to be sure the leaf springs on the other rear end are good before you go through the effort to put in a set of springs that will soon also be broken. Those old leaf springs are 69 years old, just because they might look good doesn't mean they will be after 6 months of use. Same deal with the pinion seal, the other one may well start leaking if it gets put back into service after being at rest for however many years its been sitting. You may be way ahead of the game rebuilding your springs using parts from both sets you have, If the main leaf on each side of your car is still good, with new U bolts (to bolt the axle back on the rebuilt springs) and a new center bolts (needed to replace each broken leaf in each rear spring), you can take both springs apart (leaving the good main spring on your car), and just replace the broken leafs in each spring as needed. By changing each leaf, you can inspect it for cracks (usually at the center bolt area) and wear gouges (where each leaf ends against the longer leaf above it). The center bolt holds each leaf in the spring pack together. You stack each leaf by length and by the same leaf count as the complete set onto the center bolt, clamp the leaf pact together and tighten the center bolt. Cut the excess center bolt off under the nut, and bolt the axle back on using the new U bolts. Then just replace the pinion seal on your existing rear end and bolt it back onto the rebuilt springs. If the aluminum radiator in the car works as is, maybe you can use the sheet metal around the radiator from the other car to rebuild the radiator support, if it really can to be replaced using the current radiator. It may well be the only way that radiator fits in the car was to modify the radiator support, or it could have been just hacked. You have parts you can look at and see if that can be put back onto the good car.
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