KySilverado

iTrader: (7)

I read somewhere they didn't perform very well off road. ahhh found it........



Detroit Truetrac (TT)
Based on the worm gear principal and works like clutch type positraction. Does not wear out, not recommended for tall tires over 33".

Detroit Truetracs are similar in design to the Gleason Torsen®, only the Truetracs hold up well with reasonably tall tires. They use worm wheel gears that work on the same principle as a worm gear. When the unit is loaded, the worm wheels are forced away from each other and against the case. They develop locking torque by the light friction between the worm wheels and the case. This light friction is multiplied by the ratio of the worm wheel which depends on the size of the worm wheel relative to the size of the side gear. The manufacturer can change the amount of torque biasing or lockup by simply changing the diameter of the gears, or the pitch and spiral of the teeth. A larger difference in the size for the worm wheels and side gears (smaller worm wheels and larger side gears) will increase the lockup force. Increasing the pitch and spiral of the teeth will also increase the lockup forces. Like everything, there is a limit as to how much lockup force is reasonable. Making the unit too "aggressive" will cause tire scrub during everyday driving and will cause the unit to wear out too quickly. All of the feedback that I have received from customers indicates that the unit works very well for mud and snow, while going unnoticed during every day driving. When used in situations like rocky trails where one wheel gets off the ground, the unit will not lock up 100%. Light application of the brakes will help the differential engage more transferring power to the tire that is still on the ground. For extreme situations where the vehicle will have one wheel in the air often a locking differential provides better power transfer to the wheel on the ground.

Detroit Truetracs are designed for medium duty 2WD and 4WD applications. They work well in the front and rear, and are so smooth that there is little or no hint of resistance in the steering wheel when used in front drive steering axles. Like the Gleason Torsen®, the Detroit Truetrac does not bang or clunk, has no clutch chatter, does not wear out like clutch type positractions, does not need limited slip additive, and needs no preload or clearance adjustments.

Almost sounds too good to be true doesn't it? The only drawbacks to the Truetracs are their inability to provide lockup 100% like a locking differential can. Although Gleason no longer makes the Torsen® differential, the Detroit Truetrac is a proven design that is available for many popular applications. (aftermarket) 1 yr warranty

KySilverado

iTrader: (7)

Interesting. What brand gears?

1Bear

iTrader: (1)

OEM's in the rear, with Yukon's in the front as no one listed OEM's for the front. I would have went with Precision, but they were back-ordered at the time.

04BlackGmc

iTrader: (18)

thats what most the guys use is yukons...never really heard anything bad about them..

KySilverado

iTrader: (7)

If you had it to do over would you still go 4.56? How bad is your traction issue now? Must be pretty serious to be thinking caltracks. Are you at stock ride height? How does it hook on the street? What tires do you run? What was your previous gearing? Before and after gear swap et's.

Sorry for so many questions. I'm really considering 4.56's. Think I'd risk some durability but maintaining street reasonable street tire 4wd traction is key for me.

Mr. Sandog

I'm not trying to beat a dead horse, but if you re-read the thread, two of us have upgraded from 3.73's to 4.10's and noticed a significant performance improvement.

Curious - what are your goals in upgrading?

KySilverado

iTrader: (7)

Examining all options. 4.10's will improve performance and 4.56's more so but at what cost. Potential for carnage and maybe lost traction.

Goal is 11's with present power plant. Not many are getting there with 4.10's.

1Bear

iTrader: (1)

The C3's came with 3.73's. The rear, just has the 2" blocks removed. I really don't have any good numbers to compare as I already had the 4.56's when I installed the Radix. I was spraying a 150 shot before the Radix with a window switch, set at 3100rpm and could get out of the hole with just a squeel of the tires, which gave me low 1.7 60' numbers. I believe with the torque coming in sooner, coupled with the TT3000 and the gears are just too much for street tires. I get wheel spin through most of 1'st gear. Of course I'm running plain ol'e 275/55/20 Goodyears which don't seem to grip as well as the Toyos I had before. So to sum it up, knowing how the truck is now, I think 4.10's would of actually got out the hole quicker on street tires.

Mr. Sandog

You couldn't be more wrong on this. Look at the fastest truck list - out of the first 37 trucks (all in the 9's, 10's or 11's) only one vehicle has 4.56's or higher. The rest have 4.10's, 3.73's, 3.92's, etc.

Fastest Truck List

If you want to get into the 11's you should just step up your converter. With the power you're making, you could get a triple-disk with a higher stall speed and still keep some street manners. If that doesn't do it, then you could entertain the gear swap.

Another question - do you want to be able to do 11's at the drop of a hat (i.e. street race) or just at the track? Reason I'm asking, you could have some other wheels/tires (i.e. shorter) on tap and use those for race day. You would effectively be changing your gearing, but only temporarily.

nightrunner

iTrader: (4)

actually that list hasnt been updated recently because the entry that has 5.13 gears ( 2k5squirrel) #30 was a BS entry and a joke

there is only 3 other entrys in the whole list that have 4.56 gears ( thats the highest anyone has)

EDIT: it must be recent because blacksheep is on there on top but 2k5Squirrel admitted to it being a bs run ( actually 1slow01z71 on his motorcycle i think)