Rear end on a 49 plymouth

[furby714]

Hello was just wondering what people are using on rear end swaps I wAna switch it to a more modern one the car I have us a 4 door deluxe with the original engine and trans and also can I swap out the trany to a automatic

Thanks in advance

Jose

[Plymouthy Adams]

_{NOTE......the 49 is the most narrow of the Plymouths...before dropping your axle.remove the wheels and get the actual flange to flange distance..this is step one...}

[50 coupe]

I used a ford 8.8 out of a '98 Explorer. I think it measured 59 1/4 inches???? Yes, do the measurements first. Lots of info on this site about RE swaps and sizes of various options for replacement.

[Plymouthy Adams]

might I ad to my above statemen..do get the width of the axle with the drums still on the vehicle....If you plan on running your stock wheels, which are neutral in offset..you will need to match this width.  If a bit narrow..your tires will be nearer the leaf spring if a tad wider your tires will set closer to the fender lip...these are your concerns...your model does not have a panhard rod so sway comes into play.  If you go wider..use positive offset wheels..if you get a bit narrow use a spacer or negative offset...depending on the donor..you also have the issue of driveshaft...you must also measure your pinion angle and transfer that to the donor on install including perch width and the correct size perches as most modern are for wider springs...watch some donor tubes could be in the 2.5 inch range and not the 3" of you originals axle if entertaining cut and transfer of these pads..study your very design..get familiar with all the aspects of the job including phasing the driveline...especially if you cut and modify your existing driveshaft..

[furby714]

Thanks all for yor help really apreciate it

[MarkAubuchon]

I used a 1968 plymouth road runner

[wayfarer]

On my web site I have some axle widths listed so you can compare to what you have now:

http://www.qualityengineeredcomponents.com/?page_id=1023

[furby714]

Mark and what kinda adjustment did u have to make

Thanks for the link really helps to have the meeasurements

[Plymouthy Adams]

Mark and what kinda adjustment did u have to make

Thanks for the link really helps to have the meeasurements

the exact ones mentioned above I am sure...

[Don Coatney]

Have you thought about or done the math on what differential ratio you want to install or do you just want something modern? Here is a chart listing several Mopar differential sizes.

 

[furby714]

Soo now am freaking out the oil pan had a big dent on it and when I turned the engine on it made a knocking noise n my buddy said Ooo it's hitting the oil pan so I went to take oil pan down n it has no sign of anything hitting it. So pretty much my engine is toast right ???

[Plymouthy Adams]

toast based on what discovery?

[furby714]

toast based on what discovery?

well the knocking noise or am I just over exaggerating

[Plymouthy Adams]

you making a call based on zero established data..

[greg g]

Did you happen to notice what the oil pressure gauge was reading when the engine was running???

 

By the way you might want to check out the leather bearing insert thread inthe off topic section.  There is a procedure mentioned there that might assist you in isolating your noise, if it is a bearing.

 

Actually you need to read through his comments on the linked material.

Edited September 14, 2015 by greg g

[mopar_earl]

Have you thought about or done the math on what differential ratio you want to install or do you just want something modern? Here is a chart listing several Mopar differential sizes.

Don,

You happen to have a copy of this chart for newer than 1948?

Thanks,

Earl

Edited September 14, 2015 by mopar_earl

[Plymouthy Adams]

Don,

You happen to have a copy of this chart for newer than 1948?

Thanks,

Earl

it goes through 1979....think that would qualify for newer than 1948...what specifically are you asking?

[mopar_earl]

it goes through 1979....think that would qualify for newer than 1948...what specifically are you asking?

It ends on 1948. The newer years listed are compatible axles for the 1937 to 1948 cars. I'm curious as to a listing of what newer axles are closely compatible with say, my 1952 Dodge.

The chart shows 1971 to 1979 B-body would be a closely sized axle for 1937 to 1948 cars but nothing newer than 1948 is listed.

Earl

Edited September 14, 2015 by mopar_earl

[Don Coatney]

The chart is what it is. Suggest you measure what you have and go from there.

 

[Plymouthy Adams]

It ends on 1948. The newer years listed are compatible axles for the 1937 to 1948 cars. I'm curious as to a listing of what newer axles are closely compatible with say, my 1952 Dodge.

The chart shows 1971 to 1979 B-body would be a closely sized axle for 1937 to 1948 cars but nothing newer than 1948 is listed.

Earl

 

sorry guy...the book, if it is any help to you, lists the track of the 51-54 rear as being 11/16 narrow than the 48...that will equate to 11/32nds per side..

[mopar_earl]

The chart is what it is. Suggest you measure what you have and go from there.

Thanks Don. For right now I have no plans to swap out my axle but was curious if you happened have another chart covering later years which you don't. But yes, I will measure if I decide to change axles. At least the chart you provided will give me some options on later axles. I have saved a copy.

Earl

Edited September 14, 2015 by mopar_earl

[mopar_earl]

sorry guy...the book, if it is any help to you, lists the track of the 51-54 rear as being 11/16 narrow than the 48...that will equate to 11/32nds per side..

Cool thanks for the info! I figured they wouldn't be the same. But that definitely helps. Like I told Don I would measure if I were to do a swap. I was curious as it maybe something I do once everything else is done. Mainly to get rid of the funky drum brakes for modern self adjusting brakes. Also maybe a ratio change once I learn how the car drives and how I mostly use it.

Earl

[mopar_earl]

Thanks for the measurement chart Don! I wasn't 100% if they were doing hub face to hubface and center to center on spring perches. With the chart, I know they are using the standard methods for axles measurements. The spring width and track width terms were throwing me off a bit.

Earl

Edited September 14, 2015 by mopar_earl

[Plymouthy Adams]

I have the 9 1/4 axle from a 1979 Chrysler Newport special order police interceptor installed in a 52 Plymouth....the axle is quite wide compared to stock...but with late model positive offset wheels as found on the early LHS police cars...(if you want steel wheels that is) allow for 225/60R16's to tuck into place and fit in respect tot he fender opening as factory 1952 factory wheels that are neutral in aspect.  For retrospect...I have a 90 Dakota 8 1/4 in the 51 Plymouth Suburban with a total stock look...and the 48 has a '04 Dakota rear gear in it and utilizing positive offsets on it for a similar to stock wheel well fit...

 

It is not just axle width that you have to consider it also includes the very wheel you wish to run...

[Plymouthy Adams]

lot of folks look at the backing plate for a measurement....this can be very misleading..the same axle with 9 inch brakes compared to the 10 inch brakes will only show on the backing plate distance...you need flange to flange with drums on for best results....then decide if you stick with your stock neutral wheels..the flange to flange will set the track depending only on the offset of the wheel will this vary...spring centers change from model to model...