Happy 4th all. First special thanks to MinusPrevious, letsgetthisdone, Mrfred and Tauro91 for all your help and suggestions along the way.

I had a bad experience in a local shop for brakes all the way around. Coming home from said shop I have a front drivers strut start digging into my less than 100 miles Michlin Pilot Super Sports. This lead to my first post and deciding to replace all 4 with an Ohlins R&T setup.

Pulling the rear struts came with finding out I need to replace the rear cross member to replace it from damage. Since I have to pull it and replace it, at the same time the rear diff is leaking so I figure I'll pull that too and service it. I've notice many of you that have helped me so far have your rear diff rebuilt by shep, buschar, tcomp, english racing and so on. I've read the sticky post on the differential upgrade and how it is a MUST to be done. So I am in this deep. Might as well do it right.

So from your guys experience, what should I do? You have your diff out, and are willing to send it somewhere. Who too and what should I ask to have done along with please fix my leak.

 

If letsgetthisdone chimes in, I think he has had diff work done by TRE & he recommends them

I dont see that Jacks Trans does rear diffs

 

They do not specifically say that they do but they do rear diff's for the X. Either way I rear that it is one of the best mods to do. A MUST. So I don't know if I should rebuild it or should I send it out.

I have a local trans shop I trust I would give the parts to and they could rebuild it if that is the best option. It just seems there are as good if not better shop alternatives.

 

I would certainly only send it to Jon at TRE. Restacking the stock plates pales in comparison to Jon's maxlock upgrade, and all of his other parts.

I also highly recommend an English racing ACD tune/flash. Just let them know you have Jon's rear diff so they can tailor the ACD tune for it. But leave the ACD stock for the first few thousand miles in the fresh rear diff, give the gears time to fully break in.

 

Again I am 4 years old here.

Step 1.) Pull the diff
Step 2.) Send diff to Jon. (Perhaps step 1a. call Jon to discuss solution)
Step 3.) Reinstall rebuilt diff by Jon.
Step 4.) Allow diff to break in properly for a few thousand miles.
Step 5.) Order ACD tune/flash from English Racing
Step 6.) Enjoy new found god-like road handling

 

TRE! he'll install a sight glass too

 

Well I've submitted my "request a quote" for TRE. On another note I ran around to, sears, Home depot and harbor freight today to pick up a 3/4" Impact ratchet, air line connections and a 3/4" to 1/2" adaptor. One bolt on the rear cross member is rusted in place and I have not been successful in removing it. Yet. I'll keep you all updated. Thank you all for the help.

 

it'll be a wait. and it's worth the wait

 

Exactly that.


IIRC, the full work up on the rear diff is in the $1100 neighborhood. All new bearings and seals, detail and shot peen ring and pinion gears; setup ring and pinion; detail, shot peen and correctly shim spider/side gears; shot peen carrier; HD side cover; 12 plate max lock; site glass rear cover; all new bolts (ring gear, carrier bearing, and rear cover); new breather; new drain and fill plugs and washer. You're basically getting a brand new unit back from Jon...lol


He also has all the parts on hand if you need additional stuff, like a new ring and pinion gear set, new carrier, new spider and side gears, etc..


Jon recommends OEM diaqueen, or redline 80w140 gear oil.

 

Awesome! I am excited! I think I will ask him to install a magnetic drain plug as well. My diff hasn't had an abused life. No hard launches or times without service. I am very interested to see what he says. I also am interested in the powder coating he offers.

What does IIRC stand for?

Does the noise level change from stock?

 

it should have one from the factory.

IIRC = if I recall correctly

noise level may change, some people report clicking.

you are really gonna enjoy how the car handles with this and the acd tune. it's pretty transformative. rear diff will handle power on, and acd tune actually impacts a lot on corner entry

 

The stock drain plug is magnetic.


No abuse is a good indicator that everything will be fine, but Mitsubishi didn't do a good job of setting up the ring and pinion gears in a lot of these diffs. So, sometimes, they need replaced even if they haven't had a hard life.


IIRC = If I recall correctly.


Noise level won't change. You may notice some clicking/clunking in tighter turns due to the tighter limited slip diff, but you're not going to have gear whine or anything like that.

 

The rear diff upgrades on the CT9A totally transform the car. Every single local has stated "I can't believe it took me this long to do this".

 

I know it's been discussed in this forum, but I too am debating on my rear diff build. Deciding either sending my diff to TRE or save some money and go with weirperformance maxgrip kit. Anyone can chime in?

 

The Weir plates fail. They don't have the proper grooving to allow oil to get in between them. It causes them to overheat and wear out. Send it to TRE.