Limited slip upgrade question

Sold some parts so buying some 5.29’s. I’m contemplating putting an actual LSD in at the same time but they aren’t cheap. The truck is just a pavement truck that does tow duty. Is the factory electronic stuff really all that bad or would it suffice? Not a fan of doing things twice but also don’t like wasting money. Thoughts?

 

For a tow mule I'd leave it alone.

 

Personally the Toyota system is fine, if you never off-road I wouldn’t waste the money. I rarely get off-road but moderate stuff the factory system is fine.

 

It is not very good, compared to even older alternatives (Haldex), but why bother if you don't use it?

 

Limited slip isn’t an off road only thing.

 

Lockers or limited slip?

Limited slip is typically mechanical, nothing electronic, nothing to actuate.

 

The powertrax limited slip is awesome, and like centex said it’s not all about off road use. Spinning tires in the rain isn’t a thing anymore with it, unless I’m trying. Same can be said for a more reassuring takeoff on wet roads when pulling a trailer, or if you get said trailer sunken in some ground you miscalculated as being dry enough. I’d spend the $700 on the LSD before the 1500+ for the gears, but if I was doing the gears I’d definitely do the LSD. Not having an LSD or a locker in a truck is pitiful to me.

 

Limited slip. Zero use for lockers on this truck.

 

Let's suppose as you said, you have a trailer stuck in a soft spot. My understanding is that the powertrax doesn't engage unless you are truly rolling and spinning. So is it really going to help in that situation, or have I misunderstood the function?

 

I’ll go against the grain here, no way I would swap gears out and not replace the factory open diff. The brake based lsd is a crappy system. If they make a Detroit true trac I’d get one in a heartbeat. 5.29 is a steep gear, running 35s or 37s?

 

34’s with steel bumpers. Runs ok around town but on the highway it’s gotta drop a gear or two for any acceleration. And towing a ~3600lb trailer it won’t do better than 4th gear no matter the speed.

 

How u gonna do burnout without LSD

 

In my experience with my powertrax, if I’m on the gas both wheels are spinning even at low speed just off throttle scenarios. The more throttle you give it the more aggressively it locks up. Where I park my travel trailer I have to back it up hill in the grass. Prior to having the LSD I’d be slipping 1 tire every time and need 4x4, with the LSD both wheels are powered and I don’t slip unless the grass is very wet and it mostly negates the need for 4x4. The LSD is a game changer IMO.

 

That’s a valid point.

 

One-wheel peel

 

That would be an epic burnout.

 

I agree. I’ve had an Auburn LSD for 100k miles and it’s one of the best things I’ve done to the truck. It works in all situations - not just off-road - and makes driving in inclement weather less stressful. We get four seasons where I’m at; I installed the LSD mostly for winter driving, but also because I hate turning a corner to merge on to a road and have a tire spin on the dirt/gravel on the side of the road, causing the traction control to go nuts and shut down the throttle for a few seconds with traffic coming up behind me.

I have a Powertrax that I will be swapping in soon as I’m curious as to the difference between the two. They are obviously different systems (cone clutch vs helical gear) but we’ll see how differently they behave in the real world.

Either way I would DEFINITELY recommend installing an LSD since you are already doing gears. I haven’t changed gearing but was more than happy to pay to install the LSD.

 

Did you ever get the PowerTrax in???
Curious to hear the comparison.

I am really wanting an LSD and am leaning toward Auburn since it is made in the states.

 

Nope. I failed. Haha. Been too busy to make schedules work with my buddy to get it installed. Hoping to have it put in by the end of the month at latest. I will report back when I do, though.

 

Good move with the 5.29s with the 34” tires. I have had that combo for the last 40K miles and love it!

Same to be said for my Powertrax Grip Pro LSD.


No way I’d regear without adding a good diff. So nice everywhere I use my truck.

 

Have you had any issues with the Auburn and is there a particular reason you are switching other than wanting to try something different?

 

I’ve got about 1500 miles since the gears without adding an LSD and I’ve had zero issues with my use case.

 

Zero issues with the auburn with over 100k miles on it. I suppose there are two reasons why I’m swapping it for the grip-pro: first being I’ve wanted a helical gear type LSD in my truck from the get-go, but the auburn was the only thing available for years. I think I prefer the driving manners of torsen-type diffs, but we will see if that holds true with the tundra.

The second reason is maintenance. The Auburn requires friction modifier that should be good for 30k; mine only last 10-15k before the diff starts to get clunky and creaky telling me it’s in need of more friction modifier (the clunky/creaky is normal for clutch type diffs with tight preload with low FM). Apparently the deeper gearing combined with my truck loading and usage shears through the FM quickly. Then the dilemma becomes whether or not I drain it every 6-9 months or simply drain off 1/2 quart and top it off with more FM - and how much? Doing a full diff service requires 2 bottles of the stuff which about doubles the price of fluid. I also prefer to use a good synthetic due to high loads and low winter temps, which Auburn cautions against. After my DREX warranty expired I started running synthetic again and found no issues. But, again, do I drain out that expensive synthetic at 10-15k intervals? Or just replace some of the FM? Apparently FM breaks down/dilutes the gear oil more quickly so a 30k interval is recommended even with synthetic. I have some High Performance Lubricants gear oil ready to go in the diffs and t case, which the company says doesn’t require FM for LSD diffs. But even Mobil 1 LS (for limited slip) requires the full 2 bottles of FM.

Honestly, the extra maintenance has been well worth the advantages of running a mechanical LSD, so I’m not complaining about it or knocking it. But now that there’s a different option available it may works better for me - however slight those advantages may be. And, yes, it’s much cheaper to just keep servicing the Auburn than have it swapped out. But I have the grip pro and am willing to pony up to see the difference.

 

If memory serves correct, my Grip Pro specs Dino oil as well. No synthetic, and no FM additive. I replace mine annually, which is 25-30K miles.

That said, I believe @snivilous has been using synthetic in his Grip Pro rear end without issue. And he has a lot more power than I do.

 

Yes, grip pro also recommends Dino oil. I've yet to get a good answer as to why that is the recommendation from Auburn and Powertrax; I had a phone conversation with an Auburn rep about it and his reply was along the lines of "it was tested with conventional oil so we recommend conventional oil". That said, I plan on running synthetic.

 

IIRC @snivilous reported better “lockup” and behavior of the powertrax LSD with dino oil than with full synthetic. That was one of the reasons i used the valvoline 80/90 in mine and have been very pleased.

 

Yea I was using amsoil synthetic initially and then switched to the Valvoline dino. I honestly can't say if I've noticed a difference between the two, though it has been longer since I've noticed an "excessive amount of slipping" from one tire.