Devir

I have procured a brand new TRD Differential (p/n 41301-JS401). This will be installed into my 1998 SC400 (5sp auto).

I need to know two important things.

1. How long will the install take for a mechanic? This is pumpkin removal, popping it open, putting in new Diff, changing bearings, closing it up, filling with oil and giving my "precious" back.

2. What type of Gear oil do I use? I had bought the Amsoil 85w-140 fluid. Is this overboard for a TRD limited slip? I also bought the Diff additive.

PS: I used all the different words for a diff to make people's future searches easier. To say the least searching was a PIA.

Biggu

iTrader: (12)

i dunno who your mechanic is but when i had a miata i could pull it put one in and be done in a little over 2 hours. main thing was to let the RTV dry. i haven't pulled a lexus diff yet but it doesent look to bad to do. as far as gear oil, if its a clutch type save your diff and go get a can of kaaz gear oil, has all additive already added to it and its the best for a clutch type.

Devir

It is a clutch based LSD. I'm just wondering the type of oil to use. Slips are very particular about the type and weight of the oil you put in there. I dont want grinding gears and a thrown sllip.

As for install time. It's too cold to install the diff myself and my house lacks a garage. Hence why i need a mechanic.

I'm wanting to get this LSD installed in a hurry to give me some extra winter traction and sideways driving :-p

Blizzy

iTrader: (-1)

TRD LSD Oil is essentially an 85w-140 blend with LSD friction additives. If you prefer not to use the TRD LSD Oil, Amsoil 85w-140 with their LSD friction additive will work. The 85w-140 will allow you to beat up on the diff and have no fear of the oil breaking down: a good thing.

The procedure will likely take more than a day for your mechanic if he does the job right. The LSD unit, needs loctite to attach to the ring gear (12 hours to set). The LSD unit and the pinion shaft will also need shimmed to ensure proper gear mesh (the shims are a dealer part that normally take a couple tries to get everything just right). Then, once everything is shimmed, the rear housing needs a high temperature silicon gasket (12 hours to set).

If you are concerned about keeping your car off the road, you might salvage a 3.26 differential from somewhere as a donor and then resale yours once the swap is complete. If your SC is garaged for the winter and you just want your baby back safe and sound in a hurry, suck it up and let your mechanic take his time to make sure both backlash and contact patch are within the factory specs. Otherwise, you will be in for more harm than good when you have premature differential failure down the line. If you had your mechanic order a differential shim kit ahead of time, the process would be expedited.

Devir

That was great information Blizzy, exactly the answer I needed.
It sounds like the process is expensive to do.

I would be better off bringing the car into a dealership and getting a loaner car for a day or two it sounds.

Blizzy

iTrader: (-1)

In general, drivetrain rebuilds are no laughing matter. If you wanted, you could swing by Northeast Indiana, and I could get you done in no time.

In reality, getting a donor differential from CL Member "Aliga" would not be a horrible idea. Your monster TRD differential could be assembled properly in due time while you drive your car, and the actual swap would take 1-2hr once the TRD was assembled.

Your 3.26 rear end is pretty well sought after. You could sell it on the classifieds for $300, easy. Turbo guys love the TALL gearing.

Devir

Heck, I love the 3.26 rear gearing. If i go to a lex dealer I'll pay tons more, but at least get a loaner to drive for the day. They've been good to me here. While I'd love to go to Indiana, the gas to drive there and back would cost me more than the LSD install itself. I'm NE coast. Though I appreciate the offer.

Going slightly off topic: I ordered the Dragon TC with the S&S headers. What goes into installing the TC? Do you drop the Tranny, or hoist the engine? Would it be wise to install the TC with the headers and exhaust rebuild?

I "think" the above would be my last questions. I've done the homework on exhaust (2.25" with xpipe, and metal stratus cats, magnaflow all the way), proper LSD, suspension, timing belt, radiator, water pump, blah blah...

Blizzy

iTrader: (-1)

With the rear end dropped for the LSD swap, the driveshaft would be free and easy to remove from the transmission and drop the trans...which is required for the TC swap. It would not be a bad idea to do them both at once.

The S&S Headers will not swap directly onto the stock SC exhaust. You will need to have an exhaust shop do the swapping of the headers and the connecting of the pipes.

2.25" duals is slightly oversized for a 250-300hp motor; but, it is a canonical mod. If you can find a shop that does mandrel bending, 2" duals will flow plenty to make 300hp. In fact, the stock GS400 exhaust is 2" mandrel bent in the front section closest to the motor. Most of the supercharged GS400 guys still use that stock piece of pipe since it is so well designed and not holding back their 375whp set ups. Regardless, I would have a good exhaust shop do your exhaust mods. It should take well less than a day to get the exhaust work done. Removing the stock headers and installing the S&S headers will be the toughest part.

Devir

Good information again. LSD and TC are best to swap at the same time.

I've heard so much about the 2.25" exhaust set up that everyone seems to be running on here. I've gone 100% magnaflow on the parts, cats, X pipe, and mufflers. I'm planning on an entire exhaust rebuild from headers to tail. Mandrel bends throughout. Budgetary i'm being forced to choose Aluminized steel for the piping. Timing belt and water pump work took $1200 from my budget.

I'm hopeing the majority of the work can be done by the end of winter and into early spring so I can participate in this years race events. I'm planning AC and Drift. Sadly the suspension will be neglected this year. I know that's important too.

I'll say Blizzy your knowledge and profesionalism is great. THanks for your wonderful advice.

nextlevelcoupe

iTrader: (1)

this is my kind of thread.... im swapping in this same 98 vvti v8 drivetrain into my 95 sc400 and will be going for the same mod list!!