Air Lockers, lsd, Detroit, truetrac advise needed

[Steve Hunt]

Originally Posted by vandiesel

Reviving old thread. Just finished my rear upgrade. Dana 60 upgraded to 35 spline axles and truetrac lsd. I noticed some popping at slow turns during breakin. Thought it might be low on oil so topped it off. Yesterday decided to put a few more breakin miles on. Did extensive crazy 8s in my parking lot. No popping or anything strange. Once it warmed up then it starts popping hard at slow turns left or right. It never got hot to the touch during breakin and I’m running mineral based 80-90 as recommended. I’ve read dozens of reports of others having this issue mostly hot rodders. Anyone know of a fix or if it’s an issue? I know the van is super heavy. I’m changing the oil at my gear installer so he can see it but if gears look good as I suspect they will not sure what to do. I reached out to Eaton already.

Might want to grab a oil sample to send to Blackstone or the like. A $25 analysis could eliminate a debate before it even starts.

[arctictraveller]

[QUOTE=vandiesel;310012 Once it warmed up then it starts popping hard at slow turns left or right. It never got hot to the touch during breakin and I’m running mineral based 80-90 as recommended. I’ve read dozens of reports of others having this issue mostly hot rodders. Anyone know of a fix or if it’s an issue? I know the van is super heavy. I’m changing the oil at my gear installer so he can see it but if gears look good as I suspect they will not sure what to do. I reached out to Eaton already.[/QUOTE]

Adding in some limited slip additive has helped some folks, but it can change the torque bias and reduce the units effectiveness. Running full synthetic oil, which is slippery-er could help too, but again, changed torque bias. I'm experiencing the same exact issues. I'll be very interested in hearing what Eaton has to say to you. They have stopped responding to me after telling me the issue can't be the TT's fault, so they are not responsible, end of conversation. Please let us know their response..............

EDIT: I just realized were discussing this in two different threads, so probably no new info.

[vandiesel]

I guess I should keep true trac issues in this thread. Changed my oil today and still have MAJOR binding and popping when I turn under power. Ford modifier did not help. Magnet plug went in during breakin with 150 miles left. When we pulled the diff cover the magnet had quite a bit of metal paste on it. I think I have read every single post on this topic out there. It appears that there must be some thing in the manufacturing of the true trac that is causing this popping at slow speed turns. Plenty of people do not notice them and others have all this binding going on. My mind keeps going to the fact that my van is really heavy and that must be the issue. But then I read over and over again of guys that have these in tow big heavy trailers all the time and never noticed them. So how can it be weight related? I have 35 inch tires and that is the one thing that keeps popping up in my head as the cause along with the weight. I would love to hear if anyone has a solution as this is the limited slip that I really want in the back. Pics of plug with paste for reference.

[TomsBeast]

Originally Posted by vandiesel

My mind keeps going to the fact that my van is really heavy and that must be the issue. But then I read over and over again of guys that have these in tow big heavy trailers all the time and never noticed them. So how can it be weight related? I have 35 inch tires and that is the one thing that keeps popping up in my head as the cause along with the weight.

additional insight:

My van has a Dana 60 w/4.10 gears and a open diff and zip locker, which essentially replaces the differential action with these notched plates and cam action ovaled holes that make it all work. I gives off a low growling sounds when going around corners, gets worse when I tow heavy, almost unnoticable when not towing, almost. Knowing how these zip lockers operate, this makes perfect sense. My wife raises an eyebrow whenever she hears it, I just ignore it, hasn't gotten better or worse in 40k miles, normal amount of metallic fuzz on the magnetic drain plug. Ring and pinions are a wear item, some of the softer ones, like Yukon, wear a little more, according to a buddy who does a lot of R&P's and boat outdrive rebuilding at his shop. So there's that.



I have the same style 'zip' or 'lunchbox' locker in my super-light Suzuki Samurai, I set this one with my friend at his shop. In fact, I'm on my second set up. Unlike the one in the 9000lb van, this one acts like a spool, until 'just enough' mismatch in wheel speed is sensed, there's a slight bind between the leaft and right wheel, the springs in the zip locker are overcome, and BAM! it ratchets past a couple teeth. It's almost startling, and I don't startle easily. I've had it apart and tried two different set ups, loose, and almost too tight, neither has given a result I can live with. Rolling into a tight turn under power, and BAM! feels like you've broken an axle!


I've had other rigs with clutch plate type LSD, and several with spools. When the LSD stops growning when going around corners, you need to check to see if it's still working, because the groan is the clutch plates being overcome, and reluctantly slipping. no more groan usually mean no friction, no friction means it's not very effective, maybe not zero, but not enough to do the job if you get stuck.



Based on my limited experience with ratchet lockers and clutch plate type LSD's, grumbling and growling doesn't mean it's falling apart, neither does a little fuzz on the mag plug. I have no experience with the gear-type Eaton Trutrack type lockers, which don't have friction plates or ratchet teeth, but the fuzz may be from the R&P. Maybe they are supposed to groan a little?

[vandiesel]

I just had a lengthy call with Randy's ring and pinion, and Eaton. According to Randy's they are having this issue with the dana 60 models only. He has 5 right now and 1 already replaced with the new one doing the same. Eaton told me only 2 warranty replacements in the last 5 years. I think the issue is staying with the end users and not getting to Eaton because the forums are full of this issue. BTW there are only 2 guys dealing with truetrac warranty issues at Eaton, with Brent Bussell being the guy I'm working with. My seller is calling me back after a tech discussion with some ideas. If it has to go back I think I will be just the other 3 people I know of who had number 2 do the exact same thing. Randy's is doing these in vans mostly like mine. Matt at Randy's has one in his truck and it is completely issue free and exhibits none of these behaviors. Eaton engineer did not know what to tell me either. These are supposed to be the same as an open until they lock up. I'll try another oil change and then I'm sending it back. Funny thing is the sterlings they are doing at Randys do not do this at all which is probably why we are not hearing about it from ujoint installs. Wish it was simple and easy.

@tomsbeast - The truetrac essentially is going bang bang bang around the corner. It feels like it is destroying itself.

[TomsBeast]

Originally Posted by vandiesel

I just had a lengthy call with Randy's ring and pinion, and Eaton. According to Randy's they are having this issue with the dana 60 models only. He has 5 right now and 1 already replaced with the new one doing the same. Eaton told me only 2 warranty replacements in the last 5 years. I think the issue is staying with the end users and not getting to Eaton because the forums are full of this issue. BTW there are only 2 guys dealing with truetrac warranty issues at Eaton, with Brent Bussell being the guy I'm working with. My seller is calling me back after a tech discussion with some ideas. If it has to go back I think I will be just the other 3 people I know of who had number 2 do the exact same thing. Randy's is doing these in vans mostly like mine. Matt at Randy's has one in his truck and it is completely issue free and exhibits none of these behaviors. Eaton engineer did not know what to tell me either. These are supposed to be the same as an open until they lock up. I'll try another oil change and then I'm sending it back. Funny thing is the sterlings they are doing at Randys do not do this at all which is probably why we are not hearing about it from ujoint installs. Wish it was simple and easy.

@tomsbeast - The truetrac essentially is going bang bang bang around the corner. It feels like it is destroying itself.

I'm bored out of my skull, at home recovering from Covid, so I did a deep internet dive into Eaton True Track's design, function, along with Torsen (a little different).



From everything I've seen, it's a geared mechanism, there's no springs or friction plates, no teeth that 'ratchet', it's gear-on-gear action only, and shouldn't make noise unless it's broken (I'd expect to see chunks at oil change) or the endplay in the worm gears is so excessive, that it binds up and makes noise. I see no mechanism by which a popping noise should be normal or acceptable in a True Track unit.


Start doing figure 8's in the parking lot until it really breaks



It sounds to me like the manufacturer has a bunch of Dana 60 carriers that were machined wrong, worm pocket too deep, or off-center. Some production manager, trying to salvage his/her job said "Awe, they're fine, ship 'em" They just haven't performed and investigation yet.

[vandiesel]

Another update. I bought truetrac from an Amazon seller that turns out are a major supplier and actually supply Randi‘s ring and pinion as well as many others. They also have a technical team on site. At their request I am going to change the oil out to redline shock oil 75W250. If this doesn’t make any changes then they have agreed to warranty my unit and allow me to get a new unit that is not a true track. There is another Torsen style gear driven limited slip on the market that I was not aware of made by Richmond. They have a 35 spline Dana 60 unit that have a few more gears and apparently run smoother. I have never seen them because they are new. They informed me that they are now selling more of these than true tracs. I’m pretty happy to find out I have an option besides a locker or open diff. I’ll report back on oil change. I guess this oil is pretty special and is what top fuel dragsters use. I’m sure a 12,000 pound van will be its match.

[vandiesel]

DANA 60 REAR 4.10 DOWN RATIO

Category: LD Differential
Part Type: Limited Slip Differentials
Model/Style: Dana 60 Standard
Details: Limited Slip Carrier-Helical Style
Differential Case Design Type: Dana 60 Standard
Brand: PowerTrax
GRIP PRO D60 35SPL 4.10 & DOWN
Differential Model: Dana 60 Standard
Spline Quantity: 35
Category: LD Differential
Part Type: Limited Slip Differentials
Model/Style: Dana 60 Standard
Details: Limited Slip Carrier-Helical Style
Title: Grip PRO
For Dana 60; 35 Spline; 4.10 Carrier and Down; Verify Spline Count; Full Float Only; For Rear Differential




Powertrax proves that you don't have to choose between the superior traction of a locking differential and smooth handling and drivability of an open differential. Powertrax Extreme Traction Systems give you the best of both worlds! Our focus has always been on offering quality products that provide maximum traction, street-ability, and easy installation.
Powertrax lockers range from the original, Lock-Right for serious straight-line performance, to the No-Slip traction system for street-able vehicles. Powertrax also offers three levels of GRIP locking differentials, ranging from the clutch-type GRIP LS with a forged steel case, the gear-driven GRIP PRO and finally the GRIP LOK for extreme traction. Powertrax products provide outstanding traction for off-road machines and race vehicles.
Powertrax is a leading manufacturer of traction adding differentials for the light truck, sport utility and the performance street rod market. Whether you want the smooth and quiet operation of the original lunchbox lockers or the strength of our GRIP mechanically actuated locking differentials, Powertrax Extreme Traction Systems are the answer!


The Powertrax Grip PRO is a gear driven limited slip differential designed to be among the strongest and most durable in the industry. It combines the smooth operation of a limited-slip differential, with the strength of a fully-machined, forged steel case. Using 3x2 spiral gear technology, the Powertrax Grip Pro delivers progressive and variable traction. Based off of throttle input, you are in control of how much traction is applied, which is great for situations where finesse is as important as extreme traction. On the road, in rain and snow, and on the track, Grip Pro is a winner!

[TomsBeast]

Originally Posted by vandiesel

Another update. I bought truetrac from an Amazon seller that turns out are a major supplier and actually supply Randi‘s ring and pinion as well as many others. They also have a technical team on site. At their request I am going to change the oil out to redline shock oil 75W250. If this doesn’t make any changes then they have agreed to warranty my unit and allow me to get a new unit that is not a true track.

That sounds like a fair remedy by the warranty guys, given the circumstances. We used Redline shockproof inside the axle housing on the Top Alcohol Dragster I used to crew on, I wouldn't doubt the TF and Funny Car teams use the stuff. I've used the heavy, medium, and light versions inside VW drag transaxles, infamous for breaking ring and pinions. The problem with it in the VW application is the ring and pinion, and transmission (sliders and sycros) are bathed in the same fluid. Super high pressure formulated, high viscosity heavy oil is great for high load gears, but not so good for shifting, the syncros and slider hubs like the fluid they were designed for.



High viscosity oil fills gaps... I hope it works

[vandiesel]

Originally Posted by TomsBeast

That sounds like a fair remedy by the warranty guys, given the circumstances. We used Redline shockproof inside the axle housing on the Top Alcohol Dragster I used to crew on, I wouldn't doubt the TF and Funny Car teams use the stuff. I've used the heavy, medium, and light versions inside VW drag transaxles, infamous for breaking ring and pinions. The problem with it in the VW application is the ring and pinion, and transmission (sliders and sycros) are bathed in the same fluid. Super high pressure formulated, high viscosity heavy oil is great for high load gears, but not so good for shifting, the syncros and slider hubs like the fluid they were designed for.



High viscosity oil fills gaps... I hope it works

I learn so much here. Thanks Tom! This was a good torsen lesson for me.

https://youtu.be/JEiSTzK-A2A