Tremec3550 reliability

[Lou1119]

My mechanic who loves to spend money,Mine, has said that the Tremec 3550 that is in my car is its Achilles heel and has suggested tha it should be replaced with a TK 600.
He has said that the 3550 will not handle the torque of the engine which is a Roush 427 SR with a rating of 520 hp ad torque at 530. What are your opinions?

Thanks

[cycleguy55]

TR-3550 rated from 350-475 lbs-ft (TREMEC TR-3550 Transmission -Modern Driveline)

TKO-600 rated at 600 lbs-ft (TREMEC TKO Transmission TKO-500 & TKO-600 -Modern Driveline)

The TR-3550 will live much longer behind 530 lbs-ft in a 2,400 pound car than it will in a 3,800 pound car - but much will depend upon how you drive it, how sticky your tires are, etc. If you're going to the drag strip with sticky slicks, then the TKO-600 is probably a good idea. If you're cruising with normal street tires the TR-3550 could last a long time.

Just my $0.02

[Mongoose930]

I had a TKO3550 in my Contemporary with a mild 428FE. I never had any problems with it other than I felt that 5th gear was too tall. I was running pretty sticky GY Billboards and wasn't shy about getting on it once in a while. I would suspect that I would break a stub axle or half shaft before I broke the 3550.

[maurice19]

Lou,

This is off subject but , do you go to Cars and Coffee over on East Bidwell on Saturdays?

A lot of guys there to talk about torque with.

Maurice

[Lou1119]

Maurice,

I plan on going but the car was tied up with the mechanic for what seemed like an eternity but is finally running like a dream. Perhaps I'll see you at the next one.

Lou

[1795]

I would concur that given the light weight of the car and how you drive the car, taking into account tires, it is not likely that you will need to replace the transmission in normal driving situations. Unless you are experiencing problems now, If it ain't broke, then don't fix it

[Large Arbor]

I run 520 HP's through my 3550 and never had an issue. Like others have said, I do not real sticky tires.

Phil

[vatdevil]

450ft/lb on very sticky A7s and less sticky NT01s, no issues. Wheel hop is more likely to break 28 spline half shafts. Put your money there if you have an 8.8 rear.

[Dwight]

My buddy has a 427 stroked to 487 making 620 hp and over 630 tq with a 3550.

NO PROBLEM in 6 yrs, thousands of miles and spinning the tires! I've spun them a few times. Rear rims are 12" wide. Motor will still light them up at 60 -70 mph.

The 3550 shifts smooth, a lot smoother than the 600 I run. If you want to sell the 3550 let me know.

I think you would be making a big mistake going with the TKO 600.

Ditto on the light car / tire comments.

Dwight

[jhv48]

Leave it be. That's one of the smoothest shifting trannys out there. If you aren't dumping the clutch with sticky tires, you should be fine.
If it breaks, then replace it with a tko 600. But only after you have the internals "massaged" by a pro shop. Otherwise, it shifts like a truck.

[Jerry Clayton]

tko 600 is probably the last trans I would put in another car-shifting problems at high rpm!!!!!!!!!!!!!

[PurpleVenom]

3550 is what's in mine. 435rwhp and 460 rwtq, now an 11 y.o. car that I've put 31,000 miles on. No issues with the tranny, but like someone said, 5th gear does seem a little tall, but I'm ok with that with 3.55 rear gears, cruising 70mph at 2200 RPM. Only issue I've had is an annoying leak, about nickel size after each drive.

[redmt]

Dwight, I still have that 3550 for sale. Make me an offer. I need to reduce the pile.
John

[Lou1119]

Thanks to everyone. I don't plan on tracking or drag racing the car; one reason is I am too dam old and just truly enjoy driving the car. However I will use the go fast pedal occasionally. I am running Michelin pilot sports; 335x35zr17's on the rear.
Thanks again,
Lou1119

[DAVID GAGNARD]

My Tremec 3350 has been in my 3200 pound 65 Mustang fastback since around 1996, behind a 331 stroker, approx. 425+ hp and torque.........over 200 drag strip passes running drag radials, 2,000+ miles on 4 different road courses so far and 35,000 street miles......

so far no problems, and I have changed the fluid in it twice.........

david

[LMH]

Read this on line. This car has a T-5 and lasted 3 years of weekends like this. I'd guess a 3550 would last a lot longer.


Larry

[mdross1]

When I put the 3550 in my car the tko600 was not on the market yet. It is silky smooth highly doubt I will ever hurt it.