4.10 w/LSD vs. 3.55 Open Dif - Gear Swap Review

DavidRam · Apr 8, 2014

If anyone is considering having this done, maybe this will help (not on tech issues, but more on the feel and performance).

Had 3.55 open dif, swapped for oem 4.10 w/oem LSD. Used Royal Purple gear oil (it's premixed with lsd additive), mini install kit, all new bearings, Mag-Hytec dif cover (I had a little issue with it fitting).

Immediately I noticed the following:

1. Smoother yet, more sensitive throttle reponse
2. Smoother shifts, less shifting and searching for gears
3. A more balanced and planted feel on acceleration
4. More engine braking, which I like (something I miss about a stick shift)
5. An overall lighter more agile feel to the truck, less bogging down

Now, if I could only speed up the 500 mile break in period!!!

Lhemi · Apr 8, 2014

The Spohn is the same OD as stock. Glad you said something, I was looking at down that same mod!

ladiesman217 · Apr 8, 2014

Having my truck with the 4.56s in it for a little more than a week.

I noticed the same thing with the engine breaking scenario.
I find my self often trying to coast up to a red light and I have to actually hit the gas for a second or I would be holding up traffic haha.

Statcher1 · Apr 8, 2014

What was the cost of the gears and everything to so the swap. Minus labor. If you don't mind me asking

Sent from the Rocket in my Pocket

DavidRam · Apr 8, 2014

Lhemi said:
The Spohn is the same OD as stock. Glad you said something, I was looking at down that same mod!

Yep, I wish it would have cuz it's a nice upgrade. Drain plug, dipstick and all.

DavidRam · Apr 8, 2014

Statcher1 said:
What was the cost of the gears and everything to so the swap. Minus labor. If you don't mind me asking

Sent from the Rocket in my Pocket

Not cheap, I'd have to check my receipts to be sure, but roughly $1,200 just for oem 4.10 gears and oem lsd (same parts as the R/T). Motive makes cheaper gears, though, see Moes.

Here are approximates:
Gears and LSD = $1,200
Diff Cover = $250
Install Kit = $30
Bearings = $150
Royal Purple Gear Oil = $60

Total = $1,690 (those are off the top of my head)

DavidRam · Apr 8, 2014

ladiesman217 said:
Having my truck with the 4.56s in it for a little more than a week.

I noticed the same thing with the engine breaking scenario.
I find my self often trying to coast up to a red light and I have to actually hit the gas for a second or I would be holding up traffic haha.

Yep, I love it! I was born and raised in Germany, so growing up and getting my license, EVERY car was manual, automatic was very rare.
Me and my friends would race our Golf GTIs around - down shift and engine break to nearly a dead stop, barely touching the breaks for the last couple feet!

DavidRam · Apr 8, 2014

Lhemi said:
The Spohn is the same OD as stock. Glad you said something, I was looking at down that same mod!

I am not saying that it won't fit. Maybe I have the odd truck... I would definitely measure first. Before you either order it or write it off.

I think you have the same kit that I am getting from Moes and maybe if we are lucky the cover will fit after the drop...

Arth · Apr 8, 2014

I am after that diff cover. My buddy has a Laramie like mine and I think the rear sway bar either gently touches or has an inch to spare from the cover.

It looks great though and I can't wait to get one.

DavidRam · Apr 8, 2014

An inch to spare would have been awesome, mine would have gently touched it, had I put it in.

MR.REMBERT · Apr 8, 2014

How do you know if you have LSD? My build sheet say "3.55 rear axle ratio" it also says "Electronic Stability Control". Is that the same as LSD?

fasthemiram12 · Apr 8, 2014

did your GF drop come with a relocation bracket? iirc they don't and that's possibly why it isn't working.

My Belltech 4" came with one and it drops the bar lower

fasthemiram12 · Apr 8, 2014

MR.REMBERT said:
"Electronic Stability Control". Is that the same as LSD?

No... It will say "Anti Spin Differential" In the Build sheet under added options

MR.REMBERT · Apr 8, 2014

Okay. Yea it says "Anti-spin Differential Rear Axle". Thanks.

DavidRam · Apr 8, 2014

fasthemiram12 said:
did your GF drop come with a relocation bracket? iirc they don't and that's possibly why it isn't working.

My Belltech 4" came with one and it drops the bar lower

I don't think it did. That is a great point.
But my greatest concern is not it not fitting now, but rather will it fit with a 2/4 Belltech drop kit... I think it could because I am doing the upper and lower control arms, but not sure.

Does anyone with a 2012 RCSB 2x2, have a 2/4 drop and the Meg-Hytec diff cover???

DavidRam · Apr 8, 2014

Technically, I could "make" it fit with the adjustable control arms... right?

Darkflow · Apr 8, 2014

Check to see if your wheels are centered right now. When you lower it, the rear tends to shift forward. The lower control arms just re-center it but if you are centered now and may touch. You still may touch with the lower control arms. My guess would be the rear isn't centered dead on right now though. Most aren't from the factory.

DavidRam · Apr 8, 2014

DavidRam said:
But my greatest concern is not it not fitting now, but rather will it fit with a 2/4 Belltech drop kit... I think it could because I am doing the upper and lower control arms, but not sure.

Does anyone with a 2012 RCSB 2x2, have a 2/4 drop and the Meg-Hytec diff cover???

FYI, the Mag cover is 3 3/8" high (or thick or deep or whatever you call it).

I am wondering if the Mag-Hytec will fit after I put in the Belltech 2/4. :superhack:

fasthemiram12 · Apr 8, 2014

All you need is a relocation bracket

DavidRam · Apr 9, 2014

fasthemiram12 said:
All you need is a relocation bracket

Cool. I am keeping the Mag-Hytec diff cover and making it work.

1. When my truck was on the rack is when it wouldn't fit without touching the bar. But I did not try it when it was on the ground.

2. Or I will grind a little groove into the fins to make it work.

Either way, it IS going on the truck!

4.10 w/LSD vs. 3.55 Open Dif - Gear Swap Review

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Similar threads

Forum statistics

Share this page