SP GP9 page: Farr air filter box

As a consequence of the GRIP program, many locomotives (including GP9's) were fitted with a box structure on the top of the hood behind the cab to house a Farr air filter. This addition is quite noticable and is an indication that the unit has been rebuilt.

Not all units rebuilt received the box. Some early units did not have the filter added at all. During the course of the nearly ten year long program for the GP9's, units started getting the new type air filter which required the external box to house it. Later units did receive the filter modification, but it was completely internal and did not require the box. Here is a listing of SP/SSW GRIP'd GP9's known to have been so equipped.

Dennis Frazier photo - Roseburg, OR - late 1980's

Class EP418E-1:

SP 3186

SP 3187

Class EF418E-2:

SP 3388	SP 3389	SP 3390	SP 3391	SP 3392
SP 3393	SP 3394	SP 3395	SP 3396	SP 3397
SP 3398	SP 3399	SP 3400	SP 3401	SP 3402
SP 3403	SP 3404	SP 3405	SP 3406	SP 3407
SP 3408	SP 3409	SP 3410	SP 3411	SP 3412
SP 3413	SP 3414	SP 3415	SP 3416	SP 3417
SP 3418	SP 3419	SP 3420	SP 3421	SP 3422
SP 3423	SP 3424

Class EF418E-3:

SP 3755	SP 3756	SP 3757	SP 3758	SP 3759
SP 3760	SP 3761	SP 3762	SP 3763	SP 3764
SP 3765	SP 3766	SP 3767	SP 3768	SP 3769
SP 3770	SP 3771	SP 3772	SP 3773	SP 3774
SP 3775	SP 3776	SP 3777	SP 3778	SP 3779
SP 3780	SP 3781	SP 3782	SP 3783	SP 3784

Class EF418S-3:

Class EF418E-4:

SP 3816	SP 3817	SP 3818	SP 3819	SP 3820
SP 3821	SP 3822	SP 3823	SP 3824	SP 3825
SP 3826	SP 3827	SP 3828	SP 3829

Class EF418S-4:

Class EF418E-5: