Deve's Technical Network
Advance Design Chevy Trucks
(1947-1955 1st Series w/ some TF)

-----< Comments? Criticisms? Help Desk: deve@speedprint.com Open 24/7/365! >
How to Decipher Your Casting Numbers
Engine Casting Numbers Explained 1954-1962 Chevrolet









The Casting Numbers to the right are found just below and to the right of the Distributor on the passenger side. They are notoriously very hard to read and often people make the mistake of thinking a '3' is an '8'. Clean the area thoroughly and use a nice bright flashlight. This is usually a 7 digit number and each letter/number is about 1/2" tall. A little engine degreaser and a wire brush often makes this job easier.



The next numbers we need are the ones just below the Starter on the passenger side. This one will have a CONveyor Number and beside that a usually four digit letter/number combination separated like this: X XX X. For example, the first X will be a Letter from A through L. A = January through L = December. The center two digits are the day of the month. The final digit is the year the engine was made WITHIN the years that you narrowed it down to when you deciphered the Casting Numbers to the right.


The next set of numbers you will find helpful are on the flat part of the Distributor Deck. This machined flat area has serial numbers stamped into it. If you have looked very carefully and find no numbers there, chances are your block is classified as a Replacement Block and will have no numbers stamped on that deck. The numbers you are looking for are stamped (about 1/4" high) and usually a Letter followed by three Numbers and ending in another Letter (or two). The first letter is almost always F since most GM engines were made in Flint, Michigan. The following numbers are the month first followed by the day of the month. The trailing letters denote what the engine was installed in. The possible Letters for the last ones are explained in the chart below.

Serial Number/Engine Type/Series Designation
1954-1962 Chevrolet
On the flat part of the Distributor Deck you will find a stamped Serial Number. The first letter will be either F for Flint Michigan, or T for Tonowanda, New York. These were the two locations engines were manufactured at the time. The numbers behind the F (or T) designate the Calendar month and date the engine was produced. The remaining letters are in accordance to the Type and Series of the vehicle the engine came out of. This helps to tie the vehicle together with the engine. RPO's are Regular Production Orders. These standard Orders could include many variables and Chevrolet had several of them that were popular with the Dealers. Here is the Car and Truck listings for 1954-1962:

    PASSENGER CAR ID
  • A - Regular Production with Standard 3 speed or Overdrive
  • AE - Regular with heavy duty clutch (1119-1519 taxi cab)
  • B - Regular with Powerglide (Hydraulic Lifters)
  • Z - Regular Engine
  • ZC - Regular Engine with HD Clutch
  • ZH - Fleet - Aluminum Cam Gear
  • ZJ - Fleet - Aluminum Cam Gear and HD Clutch
  • Y - Automatic Transmission

    TRUCK ID (all Solid Lifter Engines)
  • J - 3100-3200-3800/CK 10-20, C30 Regular Production
  • JA - CK 10-20, C30 with RPO 311
  • JB - C10-20 with RPO 311
  • JC - 4000 (31-32-36-3800 RPO 227)/C40 CK 10-20, C30 RPO 223
  • JD - CK10-20, C30-40 with RPO 225 (HD Clutch)
  • JE - C1402 with RPO 232
  • JF - 31-32-36-38-41-4400 with RPO’s 314 & 321
  • JG - P10 Base Engine
  • JH - P10 with RPO 311
  • JK - P10 with RPO 223
  • K - 34-35-3700/P20-30
  • KA - 34-35-3700 with RPO 321/P20-30 with RPO 321
  • L - 6000/CLS50
  • LA - CS50 with RPO 225
  • LB - CLS60
  • LC - 6000 with RPO 309/CS60 with RPO 225
  • LD - 6000 with RPO 413/CL60 with RPO 413 & 585
  • LE - 6000 with RPO 413 & 309/CLS60 with RPO 350
  • LF - T60 Base Engine
  • LG - T60 with RPO 350
  • LJ - CLS60 with RPO 309
  • LK - CLS60 with RPO 350 and Powermatic
  • LM - C60 with RPO 413 & 585 and Powermatic
  • LU - CLS60 with RPO 223
  • LV - CS60 with RPO 225 and HD Clutch
  • LW - CLS60 with RPO 223 and Power Steering
  • LX - CL60 with RPO 223 and Air Brakes
  • LY - T60 with RPO 223
  • LZ - T60 with RPO 223 and Power Steering
  • M - 31-32-36-3800-4000/CK10-20, C30-40 with RPO 408
  • MA - 31-32-36-38-41-4400 with RPO 314,321 & 408
  • MB - 31-32-36-38-4000 with RPO 227 & 408/CK10-20, C30-40(RPO 409)
  • N - 5000 Regular Production/L50 with RPO 408
  • NA - 5000 with RPO 309/L60 with RPO 408
  • NC - 5000 with RPO 413
  • ND - 5000 with RPO 309 & 413/T60 with RPO 408
  • P - 6000 with RPO 408/C50-S50 with RPO 408
  • PA - 6000 with RPO’s 309 & 408/C60-S60 with RPO 408
  • PB - C50-S50 with RPO 409
  • PC - 6000 with RPO 408 & 413/C60-S60 with RPO 409
  • PD - 6000 with RPO 309, 408 & 413
  • PJ - C60 with RPO 223 & 418
  • PK - C60 with RPO 223, 408, 413-585
  • PL - C60 with RPO 223, 408, 413-585
  • PM - L60 with RPO 223 & 408
  • PN - L60 with RPO 223 & 418
  • PQ - L60 with RPO 223, 408 & 413-585
  • PR - L60 with RPO 223, 408 & 413-585
  • PS - T60 with RPO 223 & 408
  • R - 7000 Regular Production (5000 with RPO 418)
  • RA - 7000 with RPO 309 (5000 with RPO’s 309 & 418)
  • RC - 5-7000 with RPO’s 413 & 585
  • RD - 5-7000 with RPO’s 309, 413 & 585
  • S - 8000 Regular Production (6000 with RPO 418)
  • SA - 8000 with RPO 309 (6000 with RPO’s 309 & 418)
  • SC - 6-8000 with RPO’s 309, 413, 585
  • SD - 6-8000 with RPO’s 413 & 585
  • T - 9000 Regular Production (7000 with RPO 385)
  • TA - 9000 with RPO 309
  • TB - M70-C70-S70-C80 with RPO 409
  • TC - T70-T80
  • TD - C-L-70-80-M-S-70 with RPO 309
  • TE - T70-80 with RPO 309
  • TF - CL70-80, MS70, S67 with RPO 385
  • U - 10000 Regular Production (excludes 10800)
  • UA - 10000 (excludes 8800-10800) with RPO 309
  • V - R10 Base Engine
  • VA - R10 with RPO 225
  • W - R10 with RPO 667
  • WA - R10 with RPO 225 and Automatic Transmission
GM Engine Casting Numbers
(Sorted by Make/CID)

Chevrolet Casting Numbers
Number
Make
Year
CID
839910
Chevrolet
42-51
216
389770
Chevrolet
42-51
216
839770
Chevrolet
42-53
216
3835253
Chevrolet
42-53
216
3835794
Chevrolet
42-53
216
3835497
Chevrolet
42-53
216
3835849
Chevrolet
42-53
216
3897702
Chevrolet
42-53
216
3835527
Chevrolet
51
216
3835353
Chevrolet
48-52
216
3835894
Chevrolet
53
216
837751
Chevrolet
42-49
235
839931
Chevrolet
42-49
235
3693374
Chevrolet
42-49
235
3835309
Chevrolet
42-49
235
3835335
Chevrolet
42-49
235
3835374
Chevrolet
42-49
235
8397715
Chevrolet
42-49
235
3629703
Chevrolet
50-52
235
3692703
Chevrolet
50-52
235
3692708
Chevrolet
50-52
235
3692713
Chevrolet
50-52
235
3835692
Chevrolet
50-52
235
3701946
Chevrolet
53
235
3835846
Chevrolet
53
235
3835946
Chevrolet
53
235
3783949
Chevrolet
53-54
235
3701481
Chevrolet
54
235
3702436
Chevrolet
54
235
3733949
Chevrolet
55
235
3835911
Chevrolet
55
235
3843363
Chevrolet
53-55
235
3773949
Chevrolet
54
235
3835363
Chevrolet
54
235
3835491
Chevrolet
54
235
3835949
Chevrolet
54
235
3733946
Chevrolet
54-55
235
3835917
Chevrolet
54-55
235
3858190
Chevrolet
54-55
235
3856233
Chevrolet
55
235
3836223
Chevrolet
55-57
235
3836233
Chevrolet
55-57
235
3836386
Chevrolet
55-57
235
3738307
Chevrolet
58-62
235
3738476
Chevrolet
58-62
235
3739716
Chevrolet
58-62
235
3764476
Chevrolet
58-62
235
3769716
Chevrolet
58-62
235
378307
Chevrolet
60-62
235
3702436
Chevrolet
54
261
3703414
Chevrolet
54-56
261
3738813
Chevrolet
56
261
3733950
Chevrolet
55-57
261
3837012
Chevrolet
55-57
261
3836340
Chevrolet
55-62
261
3769925
Chevrolet
59-62
261
3739365
Chevrolet
58-62
261
3759365
Chevrolet
58-62
261
3769717
Chevrolet
58-62
261
3788514
Chevrolet
62-70
153
3792852
Chevrolet
62-66
194
3782856
Chevrolet
62-67
194
3782858
Chevrolet
62-67
194
3792858
Chevrolet
62-67
194
3879875
Chevrolet
62-70
194
3833057
Chevrolet
62-70
194
3833067
Chevrolet
63-70
194
3892858
Chevrolet
64-67
194
3788406
Chevrolet
62-69
230
3855991
Chevrolet
63-70
230
3921967
Chevrolet
64-69
230
9787437
Pontiac
66-67
230
386855
Chevrolet
74-77
250
3890011
Chevrolet
68-72
250
3890013
Chevrolet
68-72
250
828575
Chevrolet
72-77
250
93403466
Chevrolet
75-83
250
9790043
Pontiac
68-69
250
9795066
Pontiac
68-69
250
9890043
Pontiac
68-69
250
328572
Chevrolet
73-76
250
328575
Chevrolet
68-84
250
328576
Chevy/Buick/Pontiac
68-76
250
358825
Chevrolet
66-76
250
366855
Chevy/Buick/Olds/Pontiac
66-84
250
377127
Chevrolet/Olds/Pontiac
73-79
250
3777178
Buick
68-76
250
4001133
Chevrolet
76-80
292
1970
Chevrolet
64-67
292
289890
Chevrolet
63-77
292
328518
Chevrolet
73-77
292
328578
Chevrolet
73-84
292
328880
Chevrolet
63-77
292
239990
Chevrolet
63-77
292
352194
Chevrolet
73-84
292
364909
Chevrolet/Olds
75-79
292
377129
Chevrolet
73-84
292
3788378
Chevrolet
62-74
292
3789404
Chevrolet
63-76
292
3789412
Chevrolet
63-66
292
3789716
Chevrolet
63-72
292
3821970
Chevrolet
67-72
292
3855914
Chevrolet
63-66
292
3855987
Chevrolet
63-71
292
3851656
Chevrolet
63-72
292
3851659
Chevrolet
63-76
292
3851859
Chevrolet
63-72
292
3886061
Chevrolet
63-66
292
3921770
Chevrolet
66-76
292
3921970
Chevrolet
63-76
292
8994256
Chevrolet
64-77
292
93403467
Chevrolet
75-84
292
93406004
Chevrolet
75-84
292
GMC Casting Numbers
2135412
GMC
46-54
248, 270
2324003
GMC
55-63
270
2404929
GMC
55-63
270
2193980
GMC
52-54
302
2324004
GMC
55-62
302
2192402
GMC
Military
302
Head Casting Numbers Explained

The Head Casting number is located outside of the Valve Cover in plain site on the Drivers Side. If you have ever heard that the new style 235 gets better compression numbers with an "848" Head, look for the last three numbers of that Casting Number. I only put the numbers here that I can prove, so this is a short list.

  • 1954-1955 235 Engine 3835913
  • 1956-1962 235 Engine 3836848
  • 1956-1962 261 Engine 3836850
  • more as I encounter them
The most conscientious person I know where it comes to ultimate casting number efforts is Tim Lederman. You can find his matrix here: Tim's Casting Number Database.