M35A3 Manual Swap from Cat 3126 w/ 6spd?

[jleasure]

Manual swaps have been discussed before, but I don't see where anybody has posted detailed information about this combo. This might be a new twist.

I was reading an ad on another site that showed a 2002 Chevrolet C7500 with a Cat 3126 and 6 speed manual. My research shows that a 3126 is similar to a 3116 with many more electronic controls. Does anybody have any idea what that 6 speed trans might be? Gear ratios? I assume it would mate to a 3116. I wonder how difficult such a swap might be, how good that transmission is, and the cons of such a swap.

I really want an A3, except the auto. Any thoughts?

 

[motomacguyver]

I think you are correct that the 3216 is the same engine as the 3116 but with electronic controls. Check what the bell housing number is on the 3216, If it is an SAE #2 any thing that is a SAE # 2 will bolt right up and a SAE#3, will bolt on with an adapter plate. (Which is on the stock A3 engine to transmission interface, the 3116 has a SAE #2 bellhousing)

I would try to find out the gross vehicle weight rating of the Trans to see if it would handle the weight of an A3.

Also I would look into the rear end ratios and tire sizes of the donor truck to see if you would get what you’re looking for.

I KNOW that it would be a real "female dog" to do an AUTO trans swap, I sort of checked into it and it looks like a frame cross member would have to be moved just to get started on shoe-horning in any thing longer than the stock auto. Also a new transmission tunnel would have to be fabricated.

 

[ODdave]

I could only imagine it being an eaton 6-speed.

 

[jleasure]

That 2002 C7500 was listed as 30,000 or 32,000 GVWR as I recall. It was a dump truck. I have no idea what the rear axle ratio is. This is just one of those "what if" questions. With all of the guys here, somebody probably owns, or knows the details of such a c7500 truck/trans and might be able to chime in.

This just popped into my head as I read a classified ad. The whole idea of a manual trans A3 is attractive, but only if it is reasonably priced, can be accomplished with reasonable effort, and would yield a 55-60 top speed at an acceptable RPM. I'm not even sure that such a transmission would be any better than an A2 trans. The 6 speed caught my eye because if might have a good overdrive ratio and might have less gaps between gears.

I know that if you throw enough time and money at any project, it can work. But here, I would like cheap and simple. That combination is probably impossible.

 

[ODdave]

I think you may find it might not even be an O/D trans.

 

[jleasure]

That would be a deal breaker for sure. That thought never crossed my mind.

 

[swampzr2]

Get er done!!! There is a first for everything! I like the idea.

That 2002 C7500 was listed as 30,000 or 32,000 GVWR as I recall. It was a dump truck. I have no idea what the rear axle ratio is. This is just one of those "what if" questions. With all of the guys here, somebody probably owns, or knows the details of such a c7500 truck/trans and might be able to chime in.

This just popped into my head as I read a classified ad. The whole idea of a manual trans A3 is attractive, but only if it is reasonably priced, can be accomplished with reasonable effort, and would yield a 55-60 top speed at an acceptable RPM. I'm not even sure that such a transmission would be any better than an A2 trans. The 6 speed caught my eye because if might have a good overdrive ratio and might have less gaps between gears.

I know that if you throw enough time and money at any project, it can work. But here, I would like cheap and simple. That combination is probably impossible.

 

[wreckerman893]

It might be easier to drop the CAT and 6 speed into an A2 and do the upgrades....and it will not be nearly as ugly.

 

[spicergear]

With all 6.72:1 gearing, does anyone think the NV 5600 would hold up?

 

[jleasure]

It might be easier to drop the CAT and 6 speed into an A2 and do the upgrades....and it will not be nearly as ugly.

I do hate the ugly hood for sure.

 

[swampzr2]

I got used to the Frankenstein look after owning an A3 for awhile.... but I like the looks of both. The A3 does look tougher without mods.

I do hate the ugly hood for sure.

 

[ODdave]

With all 6.72:1 gearing, does anyone think the NV 5600 would hold up?

Couple of thoughts....

Do they offer a SAE bell for a 5600?
The OD ratio is no steeper than most common OD's
VERY EXPENSIVE
Problematic by design

 

[jleasure]

Is the G56 any better than nv5600 in this application? I have a hemi Dodge 3/4 ton 4x4 with a G56. I understand it is the same as the 6 speed in the diesels with a different bell housing and clutch. Not sure how available either the G56 or NV5600 are. I suspect both are $$$$$$$.

 

[ODdave]

G56 = bada$$

 

[kennys@wi.rr.com]

It might be easier to drop the CAT and 6 speed into an A2 and do the upgrades....and it will not be nearly as ugly.

I assume the ugliness you speak of is the hood and how it tilts up at the front? Isn't the whole reason for that being the Cat motor being taller? Don't get me wrong, I would love a Kitty Cat in my truck. I know there was some one working on putting a Cat 3208 in a Deuce, now that would be a nice truck to see.

Yet one more reason for me needing a spare deuce to practice experiment with.

 

[jleasure]

Is it the height of the engine or the height of the radiator/aftercooler? If it is the engine height, you are spot on. It would turn an A2 into a franken-hood too.

I can't lie, I would love A2 looks, a nice trans, singles, CTIS, a good seat, hardtop, heater, and (the big thing) a hydro winch.

 

[Oasis-3]

I had a 1999 Freightliner with a 3126 and a eton 7 speed

 

[wmmscott]

Excuse my ignorance, but just what do you plan to do with the truck that the auto trans can't handle it? The super singles and power steering are enough to sway me away from the a2 or older.

 

[jblack6527]

Scott, I don't know about the op, but I just personally don't like driving an auto trans.

 

[mudguppy]

With all 6.72:1 gearing, does anyone think the NV 5600 would hold up?

yes. but it is too long and hard to fit onto SAE engine adapter.

Is the G56 any better than nv5600 in this application? ...

worse.

G56 = bada$$

the G56 is a mistake. it has a much taller 'L'-gear and has lubrication issues which lead to suspect reliability behind high HP and/or big GCWR.

many guys that are serious about hot-shotting with their G56 equipped trucks have swapped in 5600's. and since they are getting hard to source and too pricey, several have resorted to putting FSO's in.



another option not mentioned that's even better than the nv5600 is the ZF6; stronger, better shifting, more reliable (than early-build 5600s), and much more plentiful. but it's even longer and still tough to use in an SAE configuration.

pretty much an Eaton/FSO is the best option, or use a 5T Spicer 5 spd.