HELP Rear end differential

[R.Hodges]

So I’m to the point I need to order my rear end for my build. Quite honestly I don’t know much about what differential would be best for a street application. I want posi for sure but can someone help out with the pros and cons of these options? Sorry in advanced.

 

[melloelky]

That Detroit locker can be a little aggressive on the street for most people. They have a tendency to be a little rough in/out of turns they make noise as they lock and unlock and have an odd feel sometimes.People do use them on the street there's no doubt about that.the truetrac and trac lok are more geared towards street use.im running the trac lok from quick and haven't had any issues.my friend has the truetrac in his fox body and he hasn't had an issue either.

 

[Doug Chahoy]

If as you say STREET USE, don’t bother with all the expensive options. I got my nine from QP Mosley standard. I did order GM billet tube ends for Camaro rear brakes and the fill and drain option. Unless you may someday change your intended use of the car keep the options to a minimum. THEY COST ALOT ALREADY

 

[Doug Chahoy]

Oh and never be sorry for asking a question. That’s why we’re all here. I’ve asked some pretty lame ones myself. Better to get the answer than purchase or build wrong

 

[69hurstolds]

If your goal is to one day trailer that bad dad to the race track most of the time, then build for the future and grab the locker. Could be a bit of a nuisance on the street, but you'll be set without having to go back in there.

That said, any of them will work. With the locker, you're one step away from a spool, but with the benefit of unlocking when you're done and need to turn off the track. If you're not going to spend most of your time at the track, and more on the street, I'd move that button choice up at least one. +2 on melloelky recommendations.

Get the Truetrac or traclok for the street. A traclok is basically a clutch posi which deals with friction modifiers for the clutches. Truetrac just needs rear end lube without extra crap in it since it's a helical type posi.

IMO, a locker type is better suited for jeeps and four wheelers when rock crawling, etc., because the locker drives the wheel on the ground as you lift the corner. Truetracs won't do that. If you're going to push gobs of torque at it for racing, a locker may be exactly what you need.

How's that for a non-answer?

 

[R.Hodges]

Appreciate all of the extremely helpful information on this. I will say that 90 percent of my driving will be on the street. I’ll be at right around 450 hp or so if all goes well. I mainly want to be able to stop on the gas now and then and let both tires smoke. As lame as it might sound lol! Without losing drivability in the long run. Which if I’m understanding the comments correctly the Eaton trutrac may be my best suited option.?

 

[L92 OLDS]

I’ll be at right around 450 hp or so if all goes well. I mainly want to be able to stop on the gas now and then and let both tires smoke. Which if I’m understanding the comments correctly the Eaton trutrac may be my best suited option.?

If you’re mainly driving on the street you want some thing with clutches in it. I would stay away from lockers personally and go with a conventional posi. You are on the right track

 

[James84SS]

I have the trutrac in my Monte running around 340hp at the wheels. Have put around 5000 miles on it in the last 2 years with no issues what so ever. It does leave 2 nice black strips on the road when i mash the gas pedal.

 

[R.Hodges]

I have the trutrac in my Monte running around 340hp at the wheels. Have put around 5000 miles on it in the last 2 years with no issues what so ever. It does leave 2 nice black strips on the road when i mash the gas pedal.

Nice! I just placed my order and went with the Trutrac. Now time for the waiting game sadly. On the plus side I have all new umi suspension with front and rear coil overs,, new wilwood front brakes, new rotors, new spindles. Final pcs of the puzzle is the rearend. Also got the wilwood rear calipers. 😍 I'm extremely excited to say the least. Thanks everyone for the advice here it really helped.!

 

[69hurstolds]

Nice! I just placed my order and went with the Trutrac. Now time for the waiting game sadly. On the plus side I have all new umi suspension with front and rear coil overs,, new wilwood front brakes, new rotors, new spindles. Final pcs of the puzzle is the rearend. Also got the wilwood rear calipers. 😍 I'm extremely excited to say the least. Thanks everyone for the advice here it really helped.!

Not trying to insult your intelligence, but I know how things can get overlooked even by the most experienced. With the Truetrac, keep in mind you DO NOT want friction modifiers in the oil. Just straight up non-syn rear gear lube. Don't even get the stuff with the additives already in it. Eaton says not to use friction modifiers with the Truetrac. Food for thought.

According to Eaton about their Truetrac:

• A quality, petroleum-mineral based, GL5 rated 80w-90 gear oil should be used.
• Synthetic oils are not recommended for Truetrac applications. While some customers have found that synthetic oils works well in this application, Eaton has not confirmed under test conditions that all synthetic oils are compatible with Detroit Truetrac applications.
• Friction modifiers should not be used because they will decrease performance (reduce differential bias).