JP91

Ok people smarter than me I need an input. I've got an overdrive 4 speed trans and I want to get a granny low. The truck is a 150 with a 300 with 35s and 4.10 gears. I want to keep the gears in it. Can I swap trannys and keep my rpms low so
I'm not burning through gallons of fuel and blowing a motor. Thanks for the help

pwhughey3

my buddy did this swap on his truck. the overdrive is a piece. it's aluminum and not heavy duty at all where the 4sp granny is cast iron and will last for years.... that being said, the trans will swap in with no problem, drive shafts will be the same and everything will bolt up as it does now. you will turn more rpms on the hwy and maybe lose some mpgs but you will gain a much more durable transmission, i have the granny in mine and it has 200,000 on it and i have had no problems with it

shortride

iTrader: (1)

Depending on what you're using the truck for. The 300 6 cylinder is a very good engine. With the 4.10 and a granny transmission you should be able to climb a tree even with the 35s. What you need to be careful with is the clutch, U-joints and axles. They must be in very good condition. I would recommend a heavy duty clutch.

The only problem I ever had with the 300-6 in my '65 was that it's very difficult to find a good single barrel carburetor.

JP91

Thanks guys for te help Well the truck will be my daily driver. And my trailer dragger. And also the truck that will tug a smart mouth kids truck that pops of about that 300-6. But it has a brand new clutch in it and once I get my money in my wallet longer than 10 minutes I'm gettin an offenhouser intake and I have an autolite 2100 series two barrel. And I'm gonna get bigger universals.

trumsey07

i just did this swap with my 86 f150 300inline and it was a direct swap nothin extra needed. im runin 3.08s now but shortly am goin to 33s with 3.55s

JP91

Do you guys know what year I can go up to to get the granny low. The junk yard down the road has an 87. If the bellhousing bolt holes won't line up couldn't I just take it off and bolt it onto mine. It's out of the same motor. It's a 300 going to a 300. So that will be right.

pwhughey3

it should bolt right up, just make sure if you get it and it doesn't work you can bring it back

Good old Bill

Isn't the 87 an aluminum trans, that might take a different bell housing, but the attach bolts to the engine are probably the same.

JP91

My trans is aluminum. I thought the granny lows was cast? But it's the od trans. And the one in the junk yard is an 88 with a 302. But I was gonna unbolt the bell housing from it and use my bell housing on the granny trans. Those should be the same. It's just the four bolts I think.

pwhughey3

the granny is a cast iron trans...