FAQ |
Members List |
Social Groups |
Calendar |
Search |
Today's Posts |
#1
|
||||
|
||||
Differential question
I have a new Strange center section installed in a car, and I can't remember whether I went with their 31 spline clutch differential or TrueTrack. I bought it in 2016 and have no invoice and the vendor records don't go back that far. I only thought about this because I have to decide whether to add friction modifier--Strange says not to use friction modifier with TrueTrack...but needed with the clutch style. Is there a way to tell what I have without pulling the center section?
__________________
"If the best Mustang is the Camaro, the best Camaro is actually the Firebird" David Zenlea |
#2
|
||||
|
||||
If it has one of those big fill caps you can probably get a flexible borescope tool in there and look and see. Harbor freight has some inexpensive ones if you don't have one.
__________________
'65 Tempest 467 3650# 11.30@120.31 |
#3
|
||||
|
||||
I've noticed with the true tracs that when the car is in the air and I spin one tire, the other tire doesn't necessarily follow it exactly like a clutch style posi unit does.
Sometimes it even spins opposite of what I'm spinning the other tire. I'd like to put eye's on it to be sure like Scott said but this might give a clue. |
#4
|
||||
|
||||
could you ask strange if they normally put a tag on the housing like GM used to do, to indicate whether the additive was required? if so, the absence of such a tag would suggest you have a truetrac. if not, the absence of such a tag tells you nothing.
|
#5
|
||||
|
||||
If worst comes to worse, Refill it without the modifier.
If it chatters then add it. Having chatter will not harm the rear for a couple of spins around the block.
__________________
I do stuff for reasons. |
#6
|
||||
|
||||
The modifier won’t affect the Truetrac so if add modifier you will be covered either way.
__________________
1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
#7
|
|||
|
|||
The instructions that came with my True Trac says to use the lubricant specified by the vehicle manufacturer. This is ambiguous as my open diff required no modifier, but I could have ordered a posi which requires a modifier. I don't know who I talked to or how I got the info that the True Trac should not have the modifier added. It makes the oil slippier. Because the True Trac is a helical gear system it requires a bit of friction to operate properly.
Both tires in the air, sometimes sometimes they spun like a posi, sometimes like an open. On the street - two equal black strips.
__________________
Frank M. 75 Firebird 68 Firebird 400 RAIII 66 Chevy II 461 Pontiac in AZ |
#8
|
||||
|
||||
I thought about doing this, but it's been sitting for 6 years and might not be able to distinguish chatter from noise that's likely from stuff being dried out.
__________________
"If the best Mustang is the Camaro, the best Camaro is actually the Firebird" David Zenlea |
#9
|
||||
|
||||
I'm no expert but this looks like a clutch style differential and not a TrueTrac. Can anyone confirm from this photo?
__________________
"If the best Mustang is the Camaro, the best Camaro is actually the Firebird" David Zenlea |
#10
|
||||
|
||||
I can't. On GM clutch style, you can generally see a tab from the friction plate sticking up if I remember correctly. I think you can see the grid looking pattern on the tabs.
__________________
'65 Tempest 467 3650# 11.30@120.31 |
#11
|
||||
|
||||
The True Trac is a worm gear system or spin-off of the Torsen design. It isn't going to care one way or the other what type of lubricant you use.
I'd put the additive in the gear oil and go on to worry about something else. A couple more comments about the Torsen design. They are fully mechanical and eliminate the spider/side gears. When you have the vehicle jacked up turning one wheel without trying to hold the other it may act somewhat like an open diff so it is often difficult to tell if one is being used without pulling the cover to take a look. This vehicle explains the parts used and how they function. https://www.youtube.com/watch?v=JEiSTzK-A2A
__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
The Following User Says Thank You to Cliff R For This Useful Post: | ||
#12
|
|||
|
|||
Here is the Eaton Truetrac video .
https://www.youtube.com/watch?v=lZmsY2YvVsc The six bolt heads on each end could be used to identify it. My truetrac came with an excellent owners manual that covers all of the Eaton diffs. It specifically recommends mineral based GL5 80w90 gear oil for the truetrac. Synthetic gear oil is not recommended and it also states that friction modifiers should not be used for the truetrac as they will decrease performance (reduce the differential bias ) . |
#13
|
||||
|
||||
Quote:
__________________
1966 Pontiac GTO (restoration thread) 1998 BMW 328is (track rat) 2023 Subaru Crosstrek Limited (daily) View my photos: Caught in the Wild |
#14
|
||||
|
||||
They may say that, but I don’t believe it since there are no clutches or cones.
__________________
1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
Reply |
Thread Tools | |
Display Modes | |
|
|