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OLYELLER · Post by **OLYELLER** » December 6, 2007, 9:20 pm

I have a 390 w/ T18 now, and would like to get a little more top end out of her. I saw someone on here put a T5 in. What other mods are neccessary for that swap? love the stick just not the 55 mph at 3800rpm :shock:

Truckfarmer · Post by **Truckfarmer** » December 6, 2007, 10:39 pm

Since you have a low first gear, have you considered just swapping the rearend gears? Maybe somewhere between 2.75 to about 3.25. That will bring the RPM's down.

cdherman · Post by **cdherman** » December 6, 2007, 11:48 pm

T-18 has a nasty spread between first and second gear, making it a poor choice for mating to a higher rear (like 3.25 or 3.00)

You end up needing to slip the clutch to get going in 2nd and 1st is still too low to be useable.

T5 is definitely interesting -- would need to be one of the "world class" units to use with a 390.

I have no idea if a correct bell can be found for a 390 (FE) pattern. I assume yes, but don't really know.

OLYELLER · Post by **OLYELLER** » December 7, 2007, 1:06 am

i'm sure the bell housing isn't a prob. I'm more woried about the clutch, like what i'll have to change??? My truck has a dana 60 and i have no idea what ratio it has. i'm sure it is up there though. gramps towed alot and was always hauling something around.

norville · Post by **norville** » December 7, 2007, 5:13 am

I put in a ford TOD aka 170-rts it's a 4spd tranny with the 4th being OD. It was an easy swap I had a c6 in mine. It bolted up to a truck FE bell(I have a 390). I did have to get a 28 spline yoke and have the short piece of my driveshaft lengthened.

I know it's no real toploader but so far it's holding up I cruise 70 at about 2600rpms . I have a dana 60 4:10 and 31"tires.

My tranny went out If I had a 9" rear I'd have swapped that out for a higher ##

My only complaint would be doing 30mph up hill it's hard to keep a gear 3K in 2nd pinging in 3rd.

A lot depends on what you plan to do with the truck???

bob

MadMaxetc · Post by **MadMaxetc** » December 7, 2007, 1:35 pm

Even a WC T-5 (95 Mustang) is only rated to 310ft-lbs. A nice 390 would be more than that.

I would check into a M5R2. 80's 300s had them and they can handle more power. It is a 5-speed with a .78 OD. (or is it .72?)

My 300 is pushing the limmits of the T-5.

OLYELLER · Post by **OLYELLER** » December 7, 2007, 2:48 pm

m5r2's that i found, say they fit 302 or 351. can this work for me???

MadMaxetc · Post by **MadMaxetc** » December 7, 2007, 6:18 pm

Fron what I gather the M5R2's are the standard toploader paturn, so that is OK. The shaft is the same spline count and dia as all other fords, so thats OK. I guess the only thing would be the length of the input shaft. I do not know what it is but I would guess that it would be the same.