Does a Caiman C9 acert fit in a FMTV?

Curious if a Cat C9 from a Caiman MRAP fits in place of a 3126 in a A1 FMTV? Alternator not withstanding. I see some MRAP specs showing C7 with Allison 3700 and the Caiman with a C9.

MatthewWBailey said:

Curious if a Cat C9 from a Caiman MRAP fits in place of a 3126 in a A1 FMTV? Alternator not withstanding. I see some MRAP specs showing C7 with Allison 3700 and the Caiman with a C9.

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does a C9 generally bolt in place of a c7? also will c9 computer (make sure it comes with it) talk to the allison with out an upgrade to a different Wtech? such as will you have to put different wire harness and solenoids in your allison and install a Wtech 4?

There were two versions of the Caiman, the first was based on the FMTV M1083 and has the C7. Then BAE came up with the (awful) Caiman II which has the C9 along with independent suspension.

coachgeo said:

does a C9 generally bolt in place of a c7? also will c9 computer (make sure it comes with it) talk to the allison with out an upgrade to a different Wtech? such as will you have to put different wire harness and solenoids in your allison and install a Wtech 4?

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I would not expect the frame mounts to fit but just wondering if there's enough volume in there to fit a C9. Thinking out loud. There's a lot of those power trains around I guess bc the Caimans got dropped. I doubt it would interface with the Allison without a bunch of babysitting. I see they used an exclusive cat power train on Caiman with the C9-Cx28-tcase all being cat. Probably simpler to just swap in the entire power train than trying to mate up the engine only. I ponder these things along with space travel and telekinetic powers

C9 is way too much torque for the Allison 3070 or 3700. Both are officially rated at 860 Ft/lbs and according to sources at Allison that FMTV owners have spoken with it is considered OK to fudge that up by another 100 Ft/lbs so at the highest rating of the C7 we are at 932 Ft/lbs of a recommended max 960 Ft/lbs input on the transmission. The C9 is like 465 HP and 1450 Ft/lbs. You would have to swap the matching transmission - which is not an Allison. So it would be a complete re-power of the truck involving a significant amount of wiring for the transmission. It would cost a LOT of time and effort. First step would be a lot of measuring to see if it would fit under the cab - which I doubt since the C7 doesn't even have enough room to accommodate the updated crankcase breather that stops them from dumping the last two quarts of oil out the breather on the freeway, The 3126b breather actually rubs on the bottom of the cab....... I doubt it would be easy and frankly the C7 at 370/932 has plenty of power so I don't really see the justification.

The marine C9 is the most expensive small engine I have ever operated.

This is why I ask