3.55 gears vs 4.10s with gear vendors

[Black dawg]

3.55s truly brings out the suck in the close ratio diesel 4spd and 5spd. First and reverse are just too tall. I went from 4.10 to 3.55 in a truck that I have been driving for 22 years now. Maybe a slight drop in pulling power, but able to cruise faster and mpg is considerably better, even loaded. My plan is to fine a wide ratio zf to steal guts from, some of the 351 units had really low gears. That, along with my us gear over drive, and 3.55 should be about perfect.....and yes you will be able to cruise double od with 355, unloaded for sure.

 

[rreegg]

4.10s on the freeway puts hairs on your chest

 

[Nero]

4.10s on the freeway puts hairs on your chest

Or brown in your pants

 

[77 F-250]

The 6.9 had 3.55 with the 4 speed and 33 tires. Used the granny gear to start off. 7.3 natural had 4.10s with the NV4500 5 speed. Descent for both the woods and highway. My next revision is a ZF6 with 4.3 gears, turbo and intercooler on a 2006 f350 frame. It's all together just need time to finish.
There is a reason why the semi's have lots of gears.

 

[DaveBen]

Yes, to get heavy loads going from a stop. I owned a Kenworth C-500 with a Detroit Diesel 8-V92 and a 13 speed tranny. Under a heavy load I would start in first gear and shift three times getting through an intersection. Under no load I would start in 4th gear and get through the intersection without shifting. It is all about getting the torque to the ground to get the load moving. By the way this was back in 1981.

 

[KansasIDI]

4.10s on the freeway puts hairs on your chest

Or brown in your pants

Ahem… 5.13s? At 80 mph… all day…

 

[Cubey]

4.10s on the freeway puts hairs on your chest

Try an Econoline.
(Warning: you might go deaf)

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[Nero]

So what's it like having a solid brass pair and a pinned odometer

 

[Ruffnek7tree]

Seems like everyone's input is confirming what I've been thinking lol.. I'm not going to buy a brand new setup, instead go the scottsman route and wait for good deals lol.. it makes sense to me, have more gears and overdrive with the lower gears, use the gvo when I'm unloaded/lightly loaded and not when I'm heavily loaded.. I've seen a few used adapters for the bw1356, so I might snap one of those up, as I slowly gather parts..

I'm thinking I don't really need the electronics, it seems like they're simple enough to diy it if I get a unit without them.. my thought for the potential debacle of if it were engaged in 4x4, use a relay in conjunction with the 4x4 indicator light, that way it's harder to mistakenly engage it while in 4x4, and come up with some sort of master switch so it couldn't be engaged if I decide I need it, like someone borrowing my truck I don't trust lol..

Thanks for all the input, and like hearing it all, bs away! Lol

 

[Cubey]

Seems like everyone's input is confirming what I've been thinking lol.. I'm not going to buy a brand new setup, instead go the scottsman route and wait for good deals lol.. it makes sense to me, have more gears and overdrive with the lower gears, use the gvo when I'm unloaded/lightly loaded and not when I'm heavily loaded.. I've seen a few used adapters for the bw1356, so I might snap one of those up, as I slowly gather parts..

I'm thinking I don't really need the electronics, it seems like they're simple enough to diy it if I get a unit without them.. my thought for the potential debacle of if it were engaged in 4x4, use a relay in conjunction with the 4x4 indicator light, that way it's harder to mistakenly engage it while in 4x4, and come up with some sort of master switch so it couldn't be engaged if I decide I need it, like someone borrowing my truck I don't trust lol..

Thanks for all the input, and like hearing it all, bs away! Lol

You wil destroy a GV also in reverse if enabled. GV will sell you the electrics if you call and order.

I bought a c6 new old stock one made in the late 80s that was missing the electric stuff and a few other parts, and GV sold new stuff to go with it.

then i never installed it on the RV so it's sitting in the closet just in case I ever want it.

GV told me that old units can use cheap generic gear oil because of the clutch material used. newer ones need very specific oil. they can tell you when it was made based on the serial number on it.

 

[Black dawg]

You wil destroy a GV also in reverse if enabled. GV will sell you the electrics if you call and order.

I bought a c6 new old stock one made in the late 80s that was missing the electric stuff and a few other parts, and GV sold new stuff to go with it.

then i never installed it on the RV so it's sitting in the closet just in case I ever want it.

GV told me that old units can use cheap generic gear oil because of the clutch material used. newer ones need very specific oil. they can tell you when it was made based on the serial number on it.

Gv can break in reverse even if not engaged. It is the weak spot in them.....other than hanging a mile off the back of the t case.....steep driveshaft angles and/or wheel hop is bad for them.

 

[Cubey]

Gv can break in reverse even if not engaged. It is the weak spot in them.....other than hanging a mile off the back of the t case.....steep driveshaft angles and/or wheel hop is bad for them.

You need to come to a complete stop before moving in reverse. No sloppy quick shifting while still in motion. It seems like the instructions mention that?

It's good advice in general, because it's h.ard the transmission if you don't.

 

[Black dawg]

My wording wasnt clear. Trying to back up against any kind of resistance, whether it is backing a load, or a rock, or a curb.... Even with the gv turned off, can can break it internally.

They also hang way out there, and on trucks with 1 piece driveshafts, wheel hop can break them.

Have seen the first way happen many times, the second only a couple.

 

[Cubey]

My wording wasnt clear. Trying to back up against any kind of resistance, whether it is backing a load, or a rock, or a curb.... Even with the gv turned off, can can break it internally.

They also hang way out there, and on trucks with 1 piece driveshafts, wheel hop can break them.

Have seen the first way happen many times, the second only a couple.

Good to know. I'd probably not want GV then, at least not for my current use. I'm often off road, in pretty rough places occasionally.

The C6 RV had a LONG 2 piece driveshaft, 176" wheelbase. The van I have now has a very long 1 piece driveshaft with E4OD, 138" wheelbase.

 

[Ruffnek7tree]

then i never installed it on the RV so it's sitting in the closet just in case I ever want it.

Let me know if you get sick of it in your closet lol