• Welcome to For E Bodies Only !

    We are a community of Plymouth Cuda and Dodge Challenger owners. Join now! Its Free!

Date code for alternator

Matt L.

Well-Known Member
Joined
Jul 23, 2020
Messages
79
Reaction score
24
Is there any way to tell the date the alternator was made?

IMG_2586.jpeg


IMG_2577.jpeg


IMG_2572.jpeg


IMG_2574.jpeg
 
Assembly date code is on the pad shown in your third pic. That one looks to have been rebuilt/remanufactured and most of the date stamps were probably lost during media blasting of the case.
 
Last edited:
Assembly date code is on the pad shown in your third pic. That one looks to have been rebuilt/remanufactured and most of the debate stamps were probably lost during media blasting of the case.
Thank you....again!
 
Assembly date code is on the pad shown in your third pic. That one looks to have been rebuilt/remanufactured and most of the date stamps were probably lost during media blasting of the case.
Do you know anything about the pink markings from the factory inspection? If you zoom in on the right hand side you can also see a little yellow to the left of the pink.

IMG_2123.jpeg


IMG_2122.jpeg
 

As Floyd notes, this alternator looks to have gone through a mass rebuilder process and the end shields (housing) were blasted, or more likely tumbled with metal shot, which damages the markings. The stamped part number appears to be 3438178.

Alternator number 3438178, as stamped on the identification pad, is a production alternator rated at 50 amps, and equipped with a double groove drive pulley. The service replacement part number for 3438178 is the same number, 3438178. In some cases, the service part number differs from the production part number.

The stamped date code is illegible in the picture. Rubbing graphite over the area may make the numbers more readable. It's possibly sometime in 1970.

This alternator used the rectifier (rear) end shield part number 3438204, casting number 3438201. Yours is the casting number, but the casting date marking is worn down. This shield was only made in 1969 - 1971 for 1970-1971 production though.

The drive (front) end shield is part number, 2095945, casting number 2095191. Yours is the casting number, but the casting date code marking is not in the picture. This shield was made in 1963 - 1972, but use varied some.

Alternator number 3438178 was available in all car lines, depending on accessories, etc. in 1970 and 1971.
 
Last edited:
As Floyd notes, this alternator looks to have gone through a mass rebuilder process and was blasted, or more likely tumbled with metal shot which damages the markings. The stamped part number appears to be 3438178.

Alternator number 3438178, as stamped on the identification pad, is a production alternator rated at 50 amps, and equipped with a double groove drive pulley. The service replacement part number for 3438178 is the same number, 3438178. In some cases, the service part number differs from the production part number.

The stamped date code is illegible in the picture. Rubbing graphite over the area may make the numbers more readable. It's possibly sometime in 1970.

This alternator used the rectifier (rear) end shield part number 3438204, casting number 3438201. Yours is the casting number, but the casting date marking is worn down. This shield was only made in 1969 - 1971 for 1970-1971 production though.

The drive (front) end shield is part number, 2095945, casting number 2095191. Yours is the casting number, but the casting date code marking is not in the picture. This shield was made in 1963 - 1972, but use varied some.

Alternator number 3438178 was available in all car lines, depending on accessories, etc. in 1970 and 1971.
TYVM for your thorough response. It does have the single groove pulley and appropriate part number for that. The car was restored in the early 90's and I think they actually tried to keep everything together. Do you think this would be the original alternator off of my 71 cuda w the 340 engine?

Also, is there any way to tell what day the engine was assembled?

IMG_2576.jpeg
 
TYVM for your thorough response. It does have the single groove pulley and appropriate part number for that. The car was restored in the early 90's and I think they actually tried to keep everything together. Do you think this would be the original alternator off of my 71 cuda w the 340 engine?

Also, is there any way to tell what day the engine was assembled?

View attachment 150959

Part number 3438178 is listed as originally having a double pulley for an air conditioned application. It likely has been changed, but may have been originally mated differently. With the eroded marking, and the likelihood of mixed parts through a rebuilder, it might not be your original, or all original. The single groove pulley, part number 2444478, was used on a few alternators in 1970 - 1971, including part number 3438173 (also 50 amp). The last digit in the stamping looks to be an "8", but could be a "3". If you have your broadcast sheet, the last two digits of the alternator part number is in the upper section, under "ALT".

The casting date and plant marking on the front shield is shown here:
Screenshot 2026-02-15 11.20.25 AM.png


It's hard to read, but it may be "67" which would not be on an original 1971 alternator.

The plant code, KCP, is the Kokomo, Indiana foundry, but at that time, all alternator housings were cast by Chrysler in their own foundry. Early 60s castings were done by Lester until Chrysler ramped up their facility.

The day of the alternator build cannot be determined, but the week can be if the marking is there. Only the week and year were stamped, not the day. Something like "22 - 71" would be used.
 
Rear axle markings are all over the place.

My google-foo is pretty basic, but if you enter a search for whatever topic, for example: “Mopar rear end markings” and then add “Moparts.org” or “Forebodiesonly.org” or “e-bodies.org” your top hits will be previous topics on that particular subject. There are lots of pics in those posts and a crazy amount of variations.

As for the pink marking on the axle tube, I met a guy with a low-mile T/A and his car had something similar.

A27C4748-1252-49ED-AE46-822073F55ECF.jpeg
 
Last edited:
regarding the alternator, these were designed to wear out, and be replace through the life of the car. it is pretty slick you have one that still looks like a mopar issue. but for a car to have its original alternator, seems impractical unless the things was never driven.

the axle tubes typically contain stamped letters and numbers referring to build information of the axle assemblies. the third memory may contain hand-written markings.
 
Back
Top