MadMikeB

Howdy People,

Last night my TC3 was making a horrid screeching noise, apparently from the rear end, only under heavy initial acceleration. Suspecting that a bearing might have gummed up and been spinning in its housing I just started stripping it down. Sure enough there does seem to be a dodgy bearing, which is easily replaced.

But also, I'm checking the diff for the first time as well (I bought this car second hand) and I'm a little confused. I've built a number of AE diffs for B4's and T4's and in every case, when built, the diff was tight but relatively free - you could grasp the main gear and twist one outdrive and the other outdrive would rotate in the opposite direction with little or no effort. The diff I just pulled from the TC3 is really tight - if you hold the main gear it take considerable effort to turn an outdrive. IS THIS RIGHT??? I'm guessing it shouldn't be this tight but, like I said, all my experience is with off-road diffs.

There is no crunchiness, so I believe the balls and rings are probably OK. So questions:

(a) Should you be able to rotate the outdrives easily?
(b) Should I simply rebuild the thing? If so should I replace the balls and rings?

Thanks for any advice!

MIKE

fathead

It Should definitely be easy to turn the outdrives whith the diff out of the car.

If there is no grittyness in the diff like you said the previous owner probably just tightened the diff screw up too much.
Just try lossining the diff off a half turn and see if that helps, if not then you should probably strip it down and inspect/rebuild it.
As long as the diff balls and rings look ok don't replace them just lightly lube them and use them again. For the thrust bearing balls just give them and the 2 washers a good clean and reapply the black diff grease to them when you reassemble it

MadMikeB

Cool, thanks man.

Jack Smash

iTrader: (35)

Everything pointed to a loose diff that melted and then cooled after you stop running making it hard to turn until you said it was smooth with no grittyness. I would replace everything but the large carbide balls.

Aries326

iTrader: (19)

I'm in the process of rebuilding 2 TC3 rollers that I picked up off of eBay and those axle roll pins are a pain in the butt to remove and install a new one. They're too damn tight. Is there an alternative besides replacing them with clamping hex drives? I'd hate to spend $20 on those darn things. Will these steel stub axle pins do the job? Here's the link:

http://www2.towerhobbies.com/cgi-bin...9&I=LXJHR8&P=K

Aries326

iTrader: (19)

Has there been a change in the TC3 transmission case? I bought 2 TC3s off eBay and the transmission cases look different. The factory TC3 that i bought, the guy changed the tranny in them - has white drive pinions and white differential ring gears. This one has a spool diff in the front. These won't fit in the Touring TC3's tranny case. There is big time binding and the gears do not spin freely at all. You have to force them to turn.

The Touring TC3 apparently has original black tranny parts. These spin in its own case and these will easily fit into the Factory TC3's tranny case.

I'm just wondering if a change was made so if there is in fact an updated tranny case that is much loosed on the inside, I would like to purchase a new one. The Factory tranny case has some stripped holes.

protc3

iTrader: (13)

around 99% of the time i have had problems with the outdrives on the tc3.they are not flat where the rings lay and they dont seem to run concentric.there was never even load on all the diff balls.i changed to aluminum outdrives and sanded the diff rings with very fine grit sand paper and the diffs were smoothe and free.polished diff rings will make you have to overtighten the diff in order for it not to slip due to the slick surface.rough them up a little with very fine sand paper and it will still be smoothe but makes it harder for the balls to slip.

Jmccormick

first in ref to the diff isues. I would not take any chances! You should just replace the diff rings and bearings along with the diff thrust balls. And I would also use either the assoc stealth diff lube or RB'S hot stuff diff lube on the diff balls and the assoc black grease on the thrust balls. And use a fine gritt piece of sand paper and take the diff rings and scuff them on a flat surface to see if they are flat if they are not you will see some high spots and you need to keep sanding untill there are no high spots. And while your at it check the cond of your outdrives if they are worn then replace them it's a good time to do it while your diffs are appart. Iwould recomend the IRS aluminum ones and also if you dont have CVDs with pin cusions you would need them with the aluminum outdrives. A poorly assembled or maintained diff will do nothing but cause headaches and affect the overall performance of your car.


Now as far as the axle roll pins go I still use the pins with my locking hex clamps. the locking clamps could still spin on the axle without them.

A neat tool to make that makes the removal and instalation of the roll pins easier is to take a pair of pliars and use a dremel and grind a slot in one of the jaws on the pliars just big enough for the roll pin to set in and the other jaw just pushes the pin in or out.

Jmccormick

They as far as I know havnt changed the design of the TC3 tranny case or gears the color of the gears does not mean anything they just used a different color dye in them.


you might want to check the shims used on the outdrives I know on my tranny cases I had to drememl some material away from the case where the outdrives go through the case for clearance from the inner race on the bearings to get them to spin freely.

Aries326

iTrader: (19)

I think they may have changed the design to the tranny cases. I just picked up a factory tc3 and there are two extra holes on them which seem to serve no purpose. I'll have to post up some pics as soon as I get home.

The factory TC3 I got has white gears instead of black that is found in my touring TC3. The factory TC3's gears won't fit in my touring TC3's gearbox but my touring TC3's gears will fit in the factory TC3's gearbox. I tried to swap them out 'cause the factory TC3 that I just bought had a 100T Spur gear and a spool gear in the front. I didn't want to run that since the pinions I have aren't right for the 100T spur gear.

Jmccormick

The extra hole in the cases I believe is so they can be used on both the TC4 and TC3 so assoc only has to manufacture one tranny case for both cars. the extra hole is for the upper brace for the front bumper on the TC4 so I guess that would be considered a change in design but as far as the actual internal dimensions they did improve them so you dont have to remove any material to free them up. but thats it as far as I know.

Jmccormick

The TC3 factory team the team version along with the TC3 RTR alnd the TC4 and TC4 RTR use the same diff gear and pinion assoc part#3914 and I have them in both colors under the same part# I do recall some of the gears being a bit thicker and they did have probs with the diff adjustment on the tC4's but I am not sure if some of the replacement gears had the same problem. But the deal with the tranny cases here are the #s for them the old number for the TC3 is assoc part#3910 the new # that covers the TC3 NTC3 and TC4 is assoc part#2368.

Aries326

iTrader: (19)

Thanks for the reply! That's exactly the info I was looking for. Looks like I'll have to swap out the tranny case in the other TC3.

Johnny Carey

iTrader: (10)

Those extra holes werent for the tc3 but they've been coming on them for about a 2 years. Those extra holes were for the NTC3 for the Front Shock Tower.

Click here

Jmccormick

I think you will see that the TC4 and NTC3 use the same front bumper upper top plate to so thats why that extra hole has been around a couple of years. My point is that ALL assoc touring cars(NTC3 FTTC3 TC3 RTR TC4 TC4 RTR) all use the same tranny cases now...........at one time the TC3 cases did NOT have the hole for the NTC3 upper bumper brace so they did have two different part #s at one time..