Locomotive Phases and Rosters - EMD/IC GP10
The GP10 is an Illinois Central rebuild of older GP-series locomotives, including the GP7, GP9, GP9B and GP18. The phases below are for the GP10 rebuilds themselves and do not reflect the phases of the original locomotives prior to rebuilding. These phases do not include GP10's rebuilt for other railroads, except for CR 7560-7575 and ADN 1810-1811. IC GP8 rebuilds followed similar phases, except with an additional division of Phase 4; see GP8 Phases.
These phases are of my own making.
Phases
Phase 1a: 1967-1968
The first few units rebuilt in 1967-1968 had inconsistent spotting features. All either had a high short hood or lacked the central air intake of later units (or both).
Phase 1b: 1969-1970
These units were very similar to Phase 2 units, except they either had a wider air filter housing, a cab-mounted headlight, or both.
- Headlight: Horizontal (on short hood) or vertical (on cab) early-style Pyle headlight
- Air filters: Horst (above roof), wide housing
- Cab roof: rounded (original GP7-GP18 profile)
Phase 2: 1969-1971
- Headlight: Horizontal early-style Pyle headlight on short hood
- IC 8184, 8318, 8322 and 8328 (perhaps others) had later-style Pyle headlight in this position.
- Air filters: Horst (above roof), narrower housing
Phase 3a: 1971-1977
- Headlight: Vertical, recessed early-style Pyle headlight on short hood
- IC 8055 had later-style Pyle headlight in this position.
Phase 3b: 1974-1977
CR 7560-7575 were similar, except with cab-mounted headlight.
- Air filters: Dynacell (on hood sides)
Phase 3c: 1977
- Headlight: Vertical, flush later-style Pyle headlight on short hood
Phase 4: 1977-1978
ADN 1810-1811 were similar, except with cab-mounted headlight.
- Cab roof: angled (later EMD style)
Other details
IC GP10's were not rebuilt in order based on their roadnumber, although most units (especially prior to about IC 8260) were rebuilt from corresponding 9000-series units (ie. 9004 became 8004 and so on). As details such as louvers, lights and grabirons varied between units, the drawings I've made of the series represent "stand-ins" for the most common variations.
Lights and air filters
- Between the number boards, units prior to Phase 3a generally had a Gyralite (with red top lens and clear bottom lens) while those after Phase 3a generally had an Oscitrol light (two clear, angled lenses above a red lens). There were many exceptions, and Phase 3a units had a mix of both light types. These lights were subsequently removed in most cases.
- Horst air filters had various housings. The vertical duct extending over the hood sides varied in height, with either an angled or rounded top. It was also absent altogether on many units (leaving only the housing on the roof).
- Dynacell air filters had a square panel that was either bolted or hinged, with the latter generally appearing on later units.
Misc. details
- Depending on the locomotives used for rebuilding, units of all phases may have front or rear fuel fillers and 36" or 48" fans.
- Some units were rebuilt from GP7's, which had cast coupler pockets/striker plates and different air reservoir piping than the GP9. Some of these units received GP9-style air reservoir piping and/or GP9 hoods.
- A few units lacked the L-shaped grabiron on the front of the short hood.
- Earlier rebuilds (up to early Phase 3a units) retained pilot footboards at both ends. These were generally replaced with flat pilot plates after the late 1970s. Late Phase 3a, most Phase 3b and all Phase 3c/Phase 4 units had either flat pilot plates at both ends, or a flat plate at the rear and plow at the front.
Roster
The following illustrates the phases of GP10 production for units with IC numbers. Fan and fuel filler variations were the result of variations in the original GP unit phases:
- A combination of 36" fans and rear fuel filler (noted simply by a dash --) was the most common arrangement, representing early GP9 or GP7 rebuilds. About 250 units had this combination.
- Any units with a front fuel filler were from later GP9 or GP18 production; some (such as 8016) received a hood with 36" fans from an older unit.
- Various combinations of hoods/roof panels and frames resulted in units that differed from as-built configurations, such as combining 48" fans with a rear fuel filler.
Rebuild dates are courtesy of the roster at illnois-central.net. A few units showed phase details inconsistent with the apparent rebuild date, in which case I have noted the date with a question mark.
| IC Number | Rebuilt | Phase | Fans, fuel filler | Notes | Drawing |
|---|---|---|---|---|---|
| 8000 | 1975 | 3b | -- | ||
| 8001 | 1969 | 2 | -- | ||
| 8002 | 1972 | 3a | -- | ||
| 8003 | 1970 | 2 | -- | ||
| 8004 | 1968 | 1a | 48" R | ||
| 8005 | 1972 | 3a | -- | ||
| 8006 | 1977 | 3a | -- | ||
| 8007 | 1972 | 3a | -- | ||
| 8008 | 1974 | 3b | -- | ||
| 8009 | 1968 | 1a | -- | ||
| 8010 | 1974 | 3a | -- | ||
| 8011 | 1973 | 3a | -- | ||
| 8012 | 1970 | 2 | -- | ||
| 8013 | 1973 | 3a | -- | ||
| 8014 | 1969 | 2 | -- | ||
| 8015 | 1977 | 3a | -- | ||
| 8016 | 1977 | 3b | 36" F | GP18 rebuild | |
| 8017 | 1973 | 3a | -- | GP7 rebuild | |
| 8018 | 1972 | 3a | -- | ||
| 8019 | 1971 | 2 | -- | ||
| 8020 | 1973 | 3a | -- | ||
| 8021 | 1974 | 3a | -- | ||
| 8022 | 1969 | 2 | 36" F | Modified fuel filler | |
| 8023 | 1971 | 2 | -- | ||
| 8024 | 1975 | 3b | -- | GP7 rebuild | |
| 8025 | 1968 | 1a | 48" R | ||
| 8026 | 1972 | 3a | -- | ||
| 8027 | 1974 | 3a | -- | ||
| 8028 | 1975 | 3b | 36" F | ||
| 8029 | 1973 | 3a | 48" F | ||
| 8030 | 1969 | 1b | -- | ||
| 8031 | 1969 | 1b | -- | ||
| 8032 | 1971 | 2 | -- | ||
| 8033 | 1971 | 2 | -- | ||
| 8034 | 1971 | 2 | -- | ||
| 8035 | 1971 | 3a | -- | ||
| 8036 | 1969 | 1b | -- | ||
| 8037 | 1974 | 3b | -- | GP7 rebuild | |
| 8038 | 1967 | 1a | -- | ||
| 8039 | 1969 | 2 | -- | ||
| 8040 | 1970 | 2 | -- | ||
| 8041 | 1971 | 2 | -- | ||
| 8042 | 1974 | 3a | -- | ||
| 8043 | 1977 | 3b | -- | GP7 rebuild | |
| 8044 | 1971 | 2 | -- | ||
| 8045 | 1970 | 3a | -- | ||
| 8046 | 1975 | 3b | -- | GP7 rebuild | |
| 8047 | 1970 | 2 | -- | ||
| 8048 | 1974 | 3a | 36" F | ||
| 8049 | 1973 | 3a | -- | GP7 rebuild | |
| 8050 | 1977 | 3c | 48" F | ||
| 8051 | 1971 | 3a | -- | ||
| 8052 | 1967 | 1a | -- | ||
| 8053 | 1972 | 3a | -- | ||
| 8054 | 1977 | 4 | -- | ||
| 8055 | 1971 | 3a | -- | Phase 3c headlight | |
| 8056 | 1970 | 2 | -- | ||
| 8057 | 1977 | 3c | -- | ||
| 8058 | 1970 | 1b | -- | ||
| 8059 | 1970 | 2 | -- | ||
| 8060 | 1969 | 1b | -- | ||
| 8061 | 1975 | 3a | -- | ||
| 8062 | 1972 | 3a | -- | ||
| 8063 | 1970 | 3a | -- | ||
| 8064 | 1969 | 2 | -- | ||
| 8065 | 1970 | 2 | -- | ||
| 8066 | 1969 | 2 | -- | ||
| 8067 | 1973 | 3a | -- | ||
| 8068 | 1970 | 2 | -- | ||
| 8069 | 1969 | 1b | -- | ||
| 8070 | 1969 | 2 | -- | ||
| 8071 | 1971 | 2 | -- | ||
| 8072 | 1968 | 2 | 48" R | ||
| 8073 | 1969 | 1b | -- | ||
| 8074 | 1973 | 3a | -- | ||
| 8075 | 1970 | 2 | -- | ||
| 8076 | 1972 | 3a | -- | ||
| 8077 | 1971 | 2 | -- | ||
| 8078 | 1971 | 2 | -- | ||
| 8079 | 1970 | 2 | -- | ||
| 8080 | 1977 | 4 | 48" F | ||
| 8081 | 1971 | 2 | -- | ||
| 8082 | 1967 | 1a | 48" R | ||
| 8083 | 1969 | 1b | -- | ||
| 8084 | 1969 | 1b | -- | ||
| 8085 | 1973 | 3a | -- | ||
| 8086 | 1977 | 4 | -- | ||
| 8087 | 1970 | 2 | -- | ||
| 8088 | 1974 | 3a | -- | ||
| 8089 | 1977 | 3c | -- | ||
| 8090 | 1975 | 3a | -- | ||
| 8091 | 1975 | 3a | -- | ||
| 8092 | 1975 | 3a | -- | GP7 rebuild | |
| 8093 | 1970 | 2 | -- | ||
| 8094 | 1972 | 3a | -- | ||
| 8095 | 1975 | 3b | -- | GP7 rebuild | |
| 8096 | 1969 | 1b | -- | ||
| 8097 | 1977 | 3b | 48" R | ||
| 8098 | 1977 | 3b | -- | ||
| 8099 | 1974 | 3a | 36" F | ||
| 8100 | 1971 | 3a | -- | ||
| 8101 | 1970 | 2 | -- | ||
| 8102 | 1970 | 2 | -- | ||
| 8103 | 1970? | 3b | -- | ||
| 8104 | 1975 | 3b | -- | ||
| 8105 | 1973 | 3a | -- | ||
| 8106 | 1971 | 2 | -- | ||
| 8107 | 1969 | 2 | -- | ||
| 8108 | 1972 | 3a | -- | ||
| 8109 | 1978 | 4 | 48" F | ||
| 8110 | 1974 | 3a | -- | ||
| 8111 | 1971 | 2 | -- | ||
| 8112 | 1971 | 2 | -- | ||
| 8113 | 1969 | 1b | -- | ||
| 8114 | 1971 | 2 | -- | ||
| 8115 | 1971 | 2 | -- | ||
| 8116 | 1975 | 3b | -- | GP7 rebuild | |
| 8117 | 1975 | 3b | -- | ||
| 8118 | 1973 | 3a | -- | ||
| 8119 | 1975 | 3a | -- | ||
| 8120 | 1973 | 3a | -- | ||
| 8121 | 1970 | 2 | -- | ||
| 8122 | 1974 | 3a | -- | ||
| 8123 | 1975 | 3b | -- | ||
| 8124 | 1974 | 3a | -- | ||
| 8125 | 1973 | 3a | -- | GP7 rebuild | |
| 8126 | 1977 | 3b | 48" R | Rebuilt from GP10 8158 | |
| 8127 | 1972 | 3a | -- | ||
| 8128 | 1972 | 3a | -- | ||
| 8129 | 1974 | 3a | -- | GP7 rebuild | |
| 8130 | 1977 | 3b | 48" F | ||
| 8131 | 1975 | 3a | -- | ||
| 8132 | 1975 | 3a | 36" F | ||
| 8133 | 1971 | 2 | -- | ||
| 8134 | 1969 | 2 | -- | ||
| 8135 | 1974 | 3a | 36" F | ||
| 8136 | 1977 | 3b | 48" F | ||
| 8137 | 1974 | 3a | 36" F | ||
| 8138 | 1975 | 3b | 36" F | ||
| 8139 | 1971 | 2 | -- | ||
| 8140 | 1970 | 2 | ? | ||
| 8141 | 1973 | 3a | -- | ||
| 8142 | 1969 | 1b | -- | ||
| 8143 | 1971 | 2 | -- | ||
| 8144 | 1973 | 3a | -- | ||
| 8146 | 1972 | 3a | -- | ||
| 8147 | 1977 | 3b | -- | ||
| 8148 | 1971 | 2 | -- | ||
| 8149 | 1973 | 3a | 36" F | ||
| 8150 | 1970 | 2 | -- | ||
| 8151 | 1972 | 3a | -- | ||
| 8152 | 1972 | 3a | -- | ||
| 8153 | 1977 | 3b | 48" F | ||
| 8154 | 1974 | 3a | -- | GP7 rebuild | |
| 8155 | 1972 | 3a | -- | ||
| 8156 | 1977 | 3b | -- | ||
| 8157 | 1974 | 3a | -- | ||
| 8158 | 1968 | 1a | Rebuilt to 8126 | ||
| 8159 | 1969 | 1b | -- | ||
| 8160 | 1972 | 3a | -- | ||
| 8161 | 1971 | 3a | -- | ||
| 8162 | 1972 | 3a | -- | ||
| 8163 | 1971 | 2 | -- | ||
| 8164 | 1964 (74?) | 3a | -- | ||
| 8165 | 1970 | 2 | -- | ||
| 8166 | 1970 | 2 | -- | GP7 rebuild | |
| 8167 | 1971 | 2 | -- | ||
| 8168 | 1974 | 3a | -- | ||
| 8169 | 1971 | 2 | -- | ||
| 8170 | 1971 | 2 | -- | ||
| 8171 | 1971 | 2 | -- | ||
| 8173 | 1972 | 3a | -- | ||
| 8174 | 1977 | 3c | -- | ||
| 8175 | 1970 | 2 | -- | ||
| 8176 | 1973 | 3a | -- | ||
| 8177 | 1970 | 2 | -- | ||
| 8178 | 1977 | 3b | -- | ||
| 8179 | 1971 | 2 | -- | ||
| 8180 | 1971 | 3a | -- | ||
| 8181 | 1971 | 3a | -- | ||
| 8183 | 1972 | 3a | -- | ||
| 8184 | 1971 | 2 | -- | ||
| 8186 | 1974 | 3a | 36" F | ||
| 8187 | 1971 | 2 | -- | ||
| 8188 | 1970 | 2 | -- | ||
| 8189 | 1972 | 3a | -- | ||
| 8190 | 1970 | 2 | -- | ||
| 8191 | 1969 | 2 | -- | ||
| 8192 | 1970 | 2 | -- | GP7 rebuild | |
| 8193 | 1970 | 2 | -- | ||
| 8194 | 1970 | 2 | -- | ||
| 8195 | 1970 | 1b | -- | ||
| 8196 | 1969 | 2 | -- | ||
| 8197 | 1970 | 2 | -- | ||
| 8199 | 1970 | 2 | -- | ||
| 8202 | 1975 | 3b | -- | ||
| 8203 | 1977 | 4 | -- | GP7 rebuild | |
| 8204 | 1973 | 3a | -- | ||
| 8205 | 1973 | 3a | -- | ||
| 8207 | 1973 | 3a | -- | ||
| 8209 | 1973 | 3a | -- | GP7 rebuild | |
| 8210 | 1970 | 2 | -- | ||
| 8211 | 1971 | 2 | -- | ||
| 8212 | 1971 | 2 | -- | ||
| 8213 | 1973 | 3a | 36" F | ||
| 8214 | 1977 | 3c | -- | ||
| 8215 | 1971 | 2 | -- | ||
| 8216 | 1974 | 3a | 36" F | ||
| 8217 | 1976 | 3a | -- | ||
| 8219 | 1974 | 3a | -- | ||
| 8220 | 1973 | 3a | -- | ||
| 8221 | 1974 | 3a | -- | ||
| 8222 | 1970 | 2 | -- | ||
| 8223 | 1971 | 2 | -- | ||
| 8224 | 1970 | 2 | -- | ||
| 8225 | 1970 | 2 | -- | ||
| 8226 | 1970 | 2 | -- | ||
| 8227 | 1970 | 2 | -- | ||
| 8228 | 1970 | 2 | -- | ||
| 8229 | 1972 | 3a | -- | ||
| 8230 | 1971 | 2 | -- | ||
| 8233 | 1968 | 1a | 48" R | ||
| 8234 | 1971 | 2 | -- | ||
| 8235 | 1970 | 2 | -- | ||
| 8236 | 1971 | 2 | -- | ||
| 8237 | 1974 | 3a | -- | GP7 rebuild | |
| 8240 | 1977 | 3c | -- | ||
| 8241 | 1974 | 3a | -- | ||
| 8243 | 1972 | 3a | -- | ||
| 8245 | 1973 | 3a | -- | ||
| 8247 | 1970 | 2 | -- | ||
| 8248 | 1971 | 2 | -- | ||
| 8249 | 1975 | 3a | -- | GP7 rebuild | |
| 8250 | 1970 | 2 | -- | ||
| 8251 | 1973 | 3a | 36" F | ||
| 8254 | 1971 | 2 | -- | ||
| 8256 | 1970 | 2 | -- | ||
| 8257 | 1972 | 3a | -- | ||
| 8258 | 1970 | 2 | -- | GP7 rebuild | |
| 8259 | 1970 | 2 | -- | GP7 rebuild | |
| 8260 | 1971 | 2 | -- | GP7 rebuild | |
| 8265 | 1973 | 3a | -- | ||
| 8266 | 1971 | 2 | -- | GP7 rebuild | |
| 8267 | 1971 | 2 | -- | ||
| 8268 | 1971 | 2 | -- | ||
| 8269 | 1971 | 2 | -- | GP7 rebuild | |
| 8270 | 1971 | 2 | -- | ||
| 8271 | 1972 | 3a | 36" F | ||
| 8272 | 1972 | 3a | 36" F | ||
| 8273 | 1972 | 3a | -- | ||
| 8274 | 1972 | 3a | -- | ||
| 8275 | 1972 | 3a | -- | GP7 rebuild | |
| 8276 | 1972 | 3a | -- | GP7 rebuild | |
| 8277 | 1972 | 3a | -- | GP7 rebuild | |
| 8278 | 1972 | 3a | -- | GP7 rebuild | |
| 8279 | 1972 | 3a | -- | GP7 rebuild | |
| 8280 | 1973 | 3a | -- | ||
| 8281 | 1972 | 3a | -- | GP7 rebuild | |
| 8282 | 1972 | 3a | -- | GP7 rebuild | |
| 8283 | 1974 | 3b | -- | ||
| 8285 | 1973 | 3a | -- | ||
| 8286 | 1973 | 3a | -- | ||
| 8287 | 1973 | 3a | -- | ||
| 8288 | 1973 | 3a | 36" F | ||
| 8289 | 1973 | 3a | -- | ||
| 8290 | 1973 | 3a | -- | ||
| 8291 | 1973 | 3a | -- | GP7 rebuild | |
| 8292 | 1973 | 3a | -- | GP7 rebuild | |
| 8293 | 1973 | 3a | -- | ||
| 8294 | 1973 | 3a | -- | GP7 rebuild | |
| 8295 | 1974 | 3a | -- | ||
| 8296 | 1974 | 3a | -- | ||
| 8300 | 1973 | 3a | 48" F | ||
| 8301 | 1978 | none | GP11 prototype | ||
| 8302 | 1977 | 3b | -- | ||
| 8303 | 1973 | 3a | 48" F | ||
| 8304 | 1977 | 3b? | -- | ||
| 8305 | 1977 | 3c | -- | ||
| 8306 | 1971 | 2 | 48" F | ||
| 8307 | 1974 | 3a | 48" F | ||
| 8308 | 1977 | 3b | -- | ||
| 8309 | 1977 | 4 | -- | ||
| 8310 | 1977 | 4 | -- | ||
| 8311 | 1977 | 4 | -- | ||
| 8312 | 1977 | 3c | -- | ||
| 8313 | 1974 | 3a | 48" F | ||
| 8314 | 1977 | 4 | -- | ||
| 8315 | 1977 | 4 | 48" F | ||
| 8316 | 1973 | 3a | -- | GP7 rebuild | |
| 8317 | 1975 | 3a | 48" R | GP7 rebuild | |
| 8318 | 1971 | 2 | 48" F | ||
| 8319 | 1977 | 4 | 48" F | ||
| 8320 | 1977 | 3c | 48" F | ||
| 8321 | 1973 | 3a | 48" F | ||
| 8322 | 1971 | 2 | 48" F | ||
| 8323 | 1977 | 4 | -- | ||
| 8324 | 1977 | 4 | -- | Rebuilt from GP10 8443 | |
| 8325 | 1977 | 3c | -- | ||
| 8326 | 1972 | 3a | 48" F | ||
| 8327 | 1972 | 3a | 48" F | ||
| 8328 | 1971 | 2 | 48" F | ||
| 8329 | 1973 | 3a | -- | ||
| 8330 | 1977 | 4 | -- | ||
| 8331 | 1977 | 4 | 48" F | ||
| 8332 | 1973 | 3a | 48" F | ||
| 8335 | 1974 | 3a | 48" R | GP7 rebuild | |
| 8337 | 1974 | 3a | 48" F | ||
| 8339 | 1974 | 3a | 48" F | ||
| 8343 | 1974 | 3a | 48" R | ||
| 8346 | 1974 | 3a | 48" R | ||
| 8347 | 1973 | 3a | 36" F | ||
| 8348 | 1971 | 2 | 48" F | ||
| 8351 | 1972 | 3a | ? | ||
| 8354 | 1975 | 3a | 48" F | ||
| 8357 | 1972 | 3a | 48" F | ||
| 8358 | 1977 | 4 | -- | ||
| 8359 | 1975 | 3b | 48" R | ||
| 8361 | 1975 | 3b | 48" R | GP7 rebuild | |
| 8362 | 1972 | 3a | 48" F | ||
| 8365 | 1974 | 3a | -- | ||
| 8370 | 1974 | 3a | 48" R | ||
| 8371 | 1974 | 3a | 48" F | ||
| 8375 | 1974 | 3a | 48" F | ||
| 8377 | 1975 | 3a | 48" F | ||
| 8379 | 1974 | 3a | 48" F | ||
| 8383 | 1974 | 3a | 48" R | GP7 rebuild | |
| 8387 | 1974 | 3a | 48" F | ||
| 8390 | 1972 | 3a | -- | ||
| 8391 | 1973 | 3a | 48" R | GP7 rebuild | |
| 8392 | 1973 | 3a | 48" R | GP7 rebuild | |
| 8393 | 1976 | 3a | -- | ||
| 8394 | 1976 | 3a | -- | ||
| 8395 | 1976 | 3a | -- | ||
| 8396 | 1976 | 3a | 36" F | ||
| 8397 | 1976 | 3a | -- | ||
| 8418 | 1974 | 3a | 48" F | GP18 rebuild | |
| 8442 | 1974 | 3a | -- | ||
| 8443 | 1974 | 3a? | Rebuilt to 8324 | ||
| 8444 | 1974 | 3a | -- | ||
| 8445 | 1974 | 3a | -- | ||
| 8446 | 1974 | 3b | -- | ||
| 8447 | 1974 | 3a | -- | ||
| 8460 | 1977 | 3a | 48" F | ||
| 8461 | 1977 | 3a | 36" F | ||
| 8462 | 1977 | 4 | -- | ||
| 8463 | 1976 | 3a | 36" F | GP7 rebuild | |
| 8464 | 1977 | 3a | 48" F | ||
| 8465 | 1976 | 3a | 36" F | GP7 rebuild | |
| 8466 | 1976 | 3a | -- |