Newbie alert! Can't identify my tranny!!

[eaglecomm]

Alright, I have been researching for the past week trying to identify the tranny in my 'new-to-me' '71 F100. I have some 'noise' in 4th gear and will need to either get it rebuilt or swap it out. I had figured that I had a NP435, but after getting right up to it, it is not a NP435.

So here are the characteristics (it is still in the truck for now because I can still drive in gears 1-3 with no problem for the time being.. though it isn't being driven b/c I need a new radiator).
- 4-speed
- Reverse on the floor shifter is up and to the left from 1st gear. (yes, left)
- I count 10 bolts on the top plate
- Side-shifting linkage

And although I can't find any other markings yet, I do see the word 'ORION' stamped on the side. I looked up ORION and only find them in relation to transfer cases. This is a 2WD truck.

The closest (and most identical looking) tranny I can find is the 3-speed 3.03. Though as I said, mine is a 4-speed. I have pictures (though as I said earlier, it is still under the truck so the pics are spread out over parts of the tranny.. if anyone is interested or if it will help).

Thanks!!

[71 LONG BED]

I sounded like a 3.03 trans until you said it was a 4 speed. Unfortunatly I don't have your answer, but I do have a link to a Ford trans forum that may be useful. The guy who runs the site forgot more than most people will ever know about Ford transmisions. Let us know what you find out. What does the VIN number say? Is it original?

Oh, by the way,

[eaglecomm]

Thanks, will check over there.
I did end up finding some lettering on it that I will be researching after I type this reply, but wanted to get it on here in case it helps anyone as they try to help me!

RUGCO MF
D8TR MA 0354

It also has some letters/numbers on the tail housing.. one of which is either 2803665-C or 2603665-C

I had looked earlier and found a TREMEC 4-speed that seemed to have some of my characteristics, but found no pictures to back me up.

Thanks again.

[spartman]

Sounds like a 4 speed toploader from a 78 car.

Possibly a RUG tranny

[eaglecomm]

Here is what I read on the tremecs.

T170F
Side mounted Overdrive (SMOD). Synchronized in all forward gears, with top loaded cast iron case. Used in 1978-84 Ford light duty pickups and vans. Similar in appearance to the Ford "top loader trans" but has overdrive 4th gear. Three shift rails mounted to the left side of case. This unit was produced for cars also but with lighter duty bearings and gear train. Produced in 2 and 4 wheel drive versions.

T170FS
Also known as Single Rail Overdrive (SROD). Has an aluminum case with shifter turret mounted on extension housing. Synchronized in all forward speeds with 4th being overdrive. Used in Ford light duty pickup trucks 1980-83. There is also a passenger car version of this unit with lighter duty bearings and gear ratios. Produced in 2 and 4 wheel drive versions.

Just need to understand the difference between Single Rail and Side Mounted Overdrive. And hope I can find a decent picture of one to match against.

[spartman]

IIRC the SROD version has the shifter coming out the top like you would expect for a 4 speed.

The SMOD has the shifter hooking up to the side of the tranny just like the Ford 3.03.

[eaglecomm]

I C. Then makes mine an SMOD.
Ok, well, thanks to you guys for helping me walk through this. I am leaning more towards it being the Tremec T170F.

Now I just have to figure out what to replace it with!

[AustinTom]

Does it have overdrive? If not then it really sounds like a 4 speed top loade out of a car.

http://cgi.ebay.com/ebaymotors/1969-for ... dZViewItem

Look at this one.

[eaglecomm]

That pretty much looks identical!!

Is there an easy way to tell if I have overdrive?

[spartman]

According to the info I have if it is an overdrive tranny the 3-4 shifter arm should be pointing the opposite direction of the 1-2 shifter arm

[AustinTom]

If you have the tranny out of the truck, you can tell by spinning the input shaft in 4th gear. If the output shaft rotates exactly 1 turn for every 1 turn of the input shaft the no od. If it rotates more than 1 turn for one turn of the input shaft, it is an overdrive tranny.

[eaglecomm]

Sorry, I love working on cars, but it is my first foray in to trannies and I can't drop the transmission out right now (never done it b4 anyways, so I may not be brave enough to try it without supervision )
Can you explain what you mean that the shifter arm is pointing in the opposite direction?

Here are 2 pics I snapped to try and get a pic of the shifter linkage.

[AustinTom]

could you post a pic of the entire transmission?

[spartman]

In your pictures you see that the "arms" on the tranny?

See where the one of them points "up" and the others point "down".

What ford did is to make the OD work in these trannies in the 3rd gear position.

So in order for it to work they inverted the shifter arm so that it would work the same.

When you were shifting into 3rd you actually were shifting into 4th and then when you shifted into OD you were actually shifting into the 3rd gear location

[eaglecomm]

I took a bunch of pics of the tranny.. but none of them are full pics since it is still installed. There are braces, exhaust tubes etc in the way.

I have attached some of the better shots. Let me know if there are specific angles that would be more helpful.

Apologies if I am posting too many pics against forum rules. Let me know and I can delete them (I think).
Thanks.