Transmission question

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Feb 25, 2008 | 10:22 PM

69 F-350

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Transmission question

I have a 3 spee Od out of a 1985 F-150 2wd . I was wanting to put it behind a Onan 6AT diesel . The engine came out of a P-350 bread truck . I runs great . I was wanting to know what the gear ratios are on the transmission . The engine has about 135 ftlbs of torque . The tranny was behind a 300 6 cyl . Iam trying to find out if this tranny will work or will I have to go to a NWC or TKO 5 speed . All help is greatly appreciated .

Feb 26, 2008 | 10:00 AM

subs1000w

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i really have no idea but what trans was behind the onan in the bread truck

if it was a ford trans it should work but it could of been a chevy trans in which case you need a chevy trans

Feb 27, 2008 | 03:42 PM

85e150

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The Ford od trans probably had 3.25/1.92/1/.78

http://www.gearzone.net/toploader.html

Pretty wide spread between 2nd and 3rd.

I'd look for a 5 speed with 1:1 5th, a Clark perhaps.

Feb 27, 2008 | 08:10 PM

69 F-350

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Thanks for the help guys . I went out to the garage and wrote down some numbers off of the transmission . The top has RF-E5TR-7222and the case has the number RF-E5TR-7006-AA, the tailshaft has RF E4TR-7A040-AA.
The tag on the tranny has(RTS ABI mf 10 )AND BELOW THAT( E4 TR BA 0327) . Can anyone decode the tansmission from these numbers.I don't like guessing at what I have . The main problem I have in the installation of this transmission is the T-19 and Np435 I have hit the crossmember of the truck . The truck I am putting this combo in is a 1954 International short bed pickup . If the cab was made like my 56 ford truck this tranny problem would not exist .If I can't use this tranny does anyone have a suggestion of another tranny that has the shifter in the center or more toward the rear of the case that would hold up to the diesel .The engine has 120 hp and 135 ftlbs of torque.

Feb 27, 2008 | 09:53 PM

85e150

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Thought you knew what you had...a Ford toploader overdrive. Does yours have the shifter coming out the top, on a rail along side the top, or side mounted with levers?

First ones up here:

http://www.motivegear.com/tech_info/...nny_guide.html

These were put behind 300 sixes with 250lb ft of torque, so you're ok there. The ratios aren't great, but with that amount of power, you've got all day to get through each gear anyway.....