Tremec 3550 into XY 351C - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

leonbray · 03-07-2004, 03:33

I'm interested in understanding what is involved in swapping the top loader for a Tremec 3550 behind my 351C 4V

Thanks

TruBlu351 · 03-07-2004, 07:25

OK - here goes. I've got a TKO waiting to go into my XD.

Firstly, the input shaft is longer than the toploader, therefore you can't use your toploader bellhousing by itself. There are 3 options for you to choose from.

1. Buy new custom bellhousing to suit tremec/351C: $350-400
Dellow Automotive in NSW - http://www.dellowauto.com.au/

2. Buy billet aluminium spacer plate from Mal Wood in QLD ~$250 from memory.
Goes between toploader bellhousing & tremec grearbox.
http://www.malwoodauto.com.au/

3. Nut case option - DON'T DO IT - machine input shaft.

Speak to the guys from the above shops - they will both tell you their option works well. I bought a new alloy bellhousing from Dellow's (they have both cable & hydraulic clutch options).

Thing's I'll be definitley checking after the bellhousing has been fitted is:
1. Gear box mounting face on bellhousing is PARALLEL with block/crank.
2. Concentricity - bellhousing will mount the gearbox input shaft EXACTLY in line with crankshaft. Both checks can easily be done with a dial gauge - see link.

http://www.5speedtransmissions.com/b...alignment.html

These important measurements will ensure long gearbox life/less worries (wearing bearings out/destroying spigot bearings in tail of crank etc). Big $$$ boxes to just slap up and install without proper checks.

Your standard toploader 10 spline clutch disc will fit your 3550 (TKO is 26 spline). I'd use a new throwout and spigot bearing. You currently using a single/twin plate clutch?

The output shaft is the same as the C4 & toploader so that should fit. May be slight issues with driveshaft length - should be OK. (TKO is 31 spline).

You have a shifter? There's the standard tremec version or plenty of aftermarket options.

Your speedo sender should work but DO NOT USE TOPLOADER SPEEDO COGS. Tremec ones are different - Can order from Dellows/Mal Wood.

Here's some links that provoide some good info on Tremecs:

http://www.5speedtransmissions.com/f...eakinProcedure

Thats about it for now! Do you already have the gearbox? or buying a secondhand one?

Here's a Tremec TR-3550/TKO instruction manual for you!! (pdf file)
http://www.ttcautomotive.com/English...-0510-0199.pdf

Tremec Home - http://www.ttcautomotive.com

Good luck! Don't hesitate with any other Q's.

Cheers

XR8 Lamah · 03-07-2004, 15:24

If your in brisbane, I'd take a trip down to Warwick (where Mal Wood is) and have a chat to the boys there. They're a good a good bunch, and its probably a good excuse to go for a bit of a drive in the XY ? :)

From what I understand they do a fair bit of work with the 3550's, so might even be good to talk to about sourcing one (if you don't have one already).

leonbray · 03-08-2004, 02:59

Thanks - I'll give Mal a call - might save a lot of heartache. I was going to pick up a box in the US in July

I'm going to use a shifter from my 70 Cougar Eliminator - Hurst - which will probably get the motor and box until I get the XY rebuilt.

Appreciate your responses - very informative - great links

Regards

TruBlu351 · 03-08-2004, 03:30

Where in the US are you going? I got my TKO from Florida for US$1350 which included shifter and heavy duty yoke.

Cheapest I could find a new 3550 for was ~US$1250.

What sort of gearbox/shifter do you presently have in your Cougar?

Cheers - hope that exchange rate keeps working for you!

leonbray · 03-09-2004, 01:15

Going to west coast - Cougar Nationals and a show in Seattle

Eliminator currently runs a toploader with Mickey Thompson shifter - separate revers lock out - but I have a Hurst to go back in it

Spoke to Mal - he can do the whole swap over (exchange box) for around $4k - drive up to Warwick and pick the car up the next day - might even get him to swap the 3.0 to 3.5 at the same time