A little more discussion of 6-speed conversions?

[sparks57]

I just started thinking... it seems as though a while back I read some discussion about an nv5600 conversion.



How much more would that cost over an nv4500 conversion?



Would the tighter gearing and beefier components be worth the extra money?



Would you get anything out of the conversion besides better towing ability?



That is the difference, right? Just that there are 6 instead of 5 in the same gear range so the gears are closer?

 

[JVanvuren]

I have just started collecting parts for this swap. A friend has a manual transmission shop and has 5 NV5600's sitting in the corner



Please note - I haven't actually done the swap yet, but have spent many hours researching it. Please keep this in mind when reading below.



Cost is substantially higher than an NV4500 swap... . driveshafts must be lengthened/shortened, you must buy a new clutch, new flywheel, new starter, new bellhousing adapter, and clutch slave cylinder. Of course, the transmission is quite a bit more expensive as well. In all, I would guess you're looking at at least $2000 over and above the cost of installing an NV4500.



Only you can make the decision about whether beefier parts and closer ratios are worth the money to you. To me, they are. I don't want to buy a newer truck with all of their new-fangled computers and sensors, yet want to maximize the performance of what I have. The closer ratios will let the truck pull a load more effortlessly. If you don't tow, I don't think I would bother with the 6-speed as it would probably slow you down overall.



Would you get anything out of the conversion aside from better towing ability? Sure... I call it coolness factor



John

 

[bgilbert]

Chris, how bout a big truck transmission- eaton fuller 9,10,13 speed or my favorite a super 10 speed. I wish I knew of someone that has done this a 1st gen. Of course you'd have to learn how to shift one of these trannies, unsyncronized so either double clutch for the rookies or no clutch. Bill

 

[sparks57]

I don't think I could handle anything more than a 6 speed!



I was just curiouse, I have no intention of doing the conversion... but just because I'm not gonna do it doesn't mean I don't want to learn about it!



Thanks for the info guys.

 

[Philip]

Of course you'd have to learn how to shift one of these trannies, unsynchronized so either double clutch for the rookies or no clutch. Bill

Not hard at all to learn. Shift slow hold a little tension against the shifter. It will slide in when it wants to.

Most 9/10 spds have a 600 rpm drop betweens gears. A 13spd has 300 rpm drop between gears.



A 13 spd works better with a lower power engine.

 

[bgilbert]

I guess there was a member with a 1 ton ford that swapped a C-series cummins in it with a 9 or 10 speed roadranger behind it. C-series man I think it was. Phillip what was it I've read in your earlier posts I've searched for that said you need the correct transmission drive ratios I believe? Do you mean your final drive ratio needs to be overdrive? I'd like to know what the ratio's are in a super 10. I know Werner used them alot and they're a big compnay so I imagine there should be a few in the big truck salvage yards. . Bill BTW Chris sorry for jumping into your post here on a different subject.

 

[skobylenski]

All I know about the 5600 is that it is HEAVY. Quite a bit more than the 4500, and it's also a lot bigger, so you have to fabricate new cross members to support the beast under there. I think the bell housing needs to be changed as well. It's a lot of work, but I remember an article in a TDR issue 3 or 4 back that had the start to finish details, as someone around here has done it. I think it took 2 guys a week solid to do it.



As for the Eaton Fuller trannys, I'd love one. A nine speed would really rock! I work for a trucking company when I'm at home, so I've already learned how to shift through the lower half of the older 10 speeds (no splitting gears yet ), as I do a lot of the yard-dog work - damn those Freightshaker Classics, ya' can't see around the left stack without hanging out the door when you're backing up



JVan - think you could get this guy to cut us a deal on the 5600's? I'd be more than willing to go for it if I had the money and time Too bad I'm a poor college student :{



Scott

 

[Philip]

Here is that old link.



https://www.turbodieselregister.com/forums/showthread.php?threadid=65610





Doing a NV5600 swap isn't that hard. You need the NV5600 bell housing/flywheel/clutch assy's. The 1st gen slave cylinder can be used with some mods. The drive shafts do not have to be modded on a $X$. The 205 transfer case bolts right on to the trans with no mods. As long as you have the manual trans 205. The auto 205 has a different input.



Myself I was having to replace a getrag. I would go with a NV5600. You have to replace the same parts no matter which trans you use. The only difference is the extra cost of the NV5600 itself.

 

[bgilbert]

Scott, don't fall out of that classic when your backing up . Gotta love those big hoods on them though. Heck if u can shift the bottom gears all ya gotta do if flip the range selector and go back through the gears. . Also the recent article in TDR about swapping 5-6 speed was in a 2nd gen truck. Bill

 

[skobylenski]

Shifting - yeah, it isn't hard, but I just haven't had the opportunity to get out on the road (probably because I don't have a CDL yet ) but I'm working on getting there in the future.



Personally I prefer the extended hood Pete's over the Freightliners, but that's just me. Too bad the company I work for runs 4 Freights, 2 Volvos, a 1986 (but newly revived) Kenworth W900B, and a cab-over Pete 6-wheeler with a 350 Cummins (damn, that thing is fun, all power and no truck to challenge it )



I couldn't remember if the swap was a 1st or 2nd Gen. , I'll blame it on exams being next week



Scott

 

[JVanvuren]

Originally posted by Philip





The drive shafts do not have to be modded on a $X$.

I am pretty sure the driveshafts will have to be changed for an NV5600. I know an NV4500 will swap right in using the stock driveshafts, but the NV5600 is substantially larger and I don't see how you could get by without new 'shafts.



John