is it possible to swap 7155 trans with older five speed in 923 truck?

[grunex125]

ok here it is, I like my old 817, would like to have another someday just from the stand point they are so simple to work on. My problem is 800 series trucks are getting hard to find on Gov planet and other sites. From what I see the 923 series five tons are almost the same as the 800 series except for the trans. my thoughts are, could a person essentially have an 900 series truck with the simpler five speed trans? would it fit or would there be a whole lot of retrofitting? I think if I'm not mistaken a BCII 350 Cummins would swap into it easier as well due to more room under the hood. Thought anyone?

 

[NDT]

The 900 series 5 ton uses a Allison MT654 transmission which is almost never the cause of problems with that series truck. That said, if you prefer shifting, and enjoy days of hard work to make it happen, it is a parts swapping exercise to remove the manual transmission, flywheel, and so forth from a dead 800 series truck and install them on the 250. The jack shaft would have to be custom made, along with the clutch pedal and linkage.

 

[Karl kostman]

OK where do I start? First off your referring to a 939 series of trucks one model of which is a 923. Second about the only thing a 939 series truck shares with the 800 series would be the cubic inches of the block and HP and possibly a few drive line components and I would say the similarity ends there. You mention a CAT 7155 Transmission, there is NO 939 series 5 ton that I have ever heard of that ever used that transmission, that trans is used in the 915 series of trucks and then only the larger models. The 939 series trucks all use the Allison 5 speed automatic and your NOT going to get much simpler than that. Does that trans ever have problems? I would guess so but at the same time 5 speed manuals can have issues also. The 939 series of trucks with the Allison have been one of my all time favorite trucks to drive and I have never once even had a hickup of an issue with the Allison, they are just plain great truck and about 400% more comfortable and drive way better than the 800 series trucks to!
KK

 

[simp5782]

If you wait a few months i will have my winter project CAT 7155 behind my 250 cummins. Both the auto and manuals have a serious hole between 3rd and 4th and 4th and 5th. I tow heavy and long distances with my 923. Both of them suck and 5 tons werent meant to climb hills at highway speeds. Once u get to 1900rpms on flatland they will hold there easily.

9spd Fuller would be better and easier in the 809 series trucks. Something really that can keep u in the powerband on a non turbo.

Sent from my SM-G860P using Tapatalk

 

[grunex125]

sorry about the mix up on the trans ID. So....my question is this now then, would the MT654 trans stand up to an extra 100 Hp? I'm running a 350 BC III in the 817 right now. It was put in to give me that extra power in soft field conditions, which is why also I won't run anything but dual wheels or floaters on the rear axles as well. I don't run on the road much, always on the job site or in the fields. If I do go to the 900 series, I'm thinking wouldn't be good if person had to do a "field fix" if a clutch pack let loose behind a 350. At least if I tear out a clutch i can push it back (suspended through the floor by my special arch) and replace plate and throw out bearing(had to do that with a throw out bearing last year) thats my thoughts anyway. maybe I'm wrong, pictures here would be very helpful in my understanding of the situation.

 

[grunex125]

would love to see pictures of that 7155 install!

 

[Lukes_deuce]

Personally, I wouldnt swap in an automatic with a Cummins 350 and plan to work it hard. Since you like the idea of a manual trans already, it would be easy to purchase the complete drive train for your new 900 series truck. Drop in the 350 with what ever transmission it comes with. My personal favorite is a 10 speed road ranger but any Eaton Fuller trans would be big upgrade from the spicer or allison. Then you would have the power, extra gears and 6 wheel drive. Im not an auto expert but I would think replacing a clutch pack out in the field would not be a fun time.

 

[grunex125]

Personally, I wouldnt swap in an automatic with a Cummins 350 and plan to work it hard. Since you like the idea of a manual trans already, it would be easy to purchase the complete drive train for your new 900 series truck. Drop in the 350 with what ever transmission it comes with. My personal favorite is a 10 speed road ranger but any Eaton Fuller trans would be big upgrade from the spicer or allison. Then you would have the power, extra gears and 6 wheel drive. Im not an auto expert but I would think replacing a clutch pack out in the field would not be a fun time.

the 817 Mod went so well for me last time can't help but want to do it again just wish there was a few more 817's available. can't do it right now but it always seems when you have the chance to do it a person cannot find the right vehicle or the right parts which is why I was asking about the 900 series trucks in the first place as they are more plentiful it would seem.

 

[grunex125]

Someday I'll have to get some pictures uploaded with my workhorse in her work clothes.

 

[simp5782]

if you are feeling frisky I have a 917 I can sell you.

 

[grendel]

I have a 916 with a 7155 for sale

 

[simp5782]

I have a 916 with a 7155 for sale

What are you wanting for it? I am looking at getting one. Or a 915, but would rather have the 16 or 20.

 

[Lukes_deuce]

What are you wanting for it? I am looking at getting one. Or a 915, but would rather have the 16 or 20.

That would be the way to go for a nice tractor. 920 with the big cam Cummins, swap in a 10 speed and maybe add a knuckle boom between the cab and winch. We can all dream right!?!

 

[Postman515]

I have a nice M920 with all the mods done and a matching lowboy for sale!

 

[simp5782]

Wayyy to rich for my blood.