79 datsun 620kc 4speed auto for ___?

[chipotle]

Hi, This is my first time owning a datsun and please bare with me.. I'm going to be commuting out of town 5 days a week in my datsun and I just discovered that my truck revs extremely high when going only 55mph and I dont even dare to take it past that... but I really need to get it to at least 65 so this is my plan...

 

I have a 1979 Datsun 620KC L20b with automatic 4speed ....... I want to find a transmission from an easy to find part's car that is an "automatic 5speed" and will bolt right up with no mods..

 

please tell me the make model and year's I should be looking for since I start school in 2 week's I need to get started asap thank you..

 

 

 

I will swap and mod later when I finish college but for now my 620 is getting flat red paint.. new white wall tire's very relaxed drop with a hula doll on the dash... cause datsun's are just cool like that...

[skunk]

:unsure: i could be wrong but i think they only made a 3 and 4 speed auto.

and the 3 speed auto on the l20 in our wagon can go 65 just fine with the roof rack and back filled with stuff.

the L engines are kinda high rev engines.

[datsunaholic]

The 4-speed auto wasn't stock to begin with. The 4-speed Auto that fits an L-series engine only came in '83-84 Maximas. And even that is not a "bolt in" mod, the transmission is longer and larger than the stock trans.

 

The original was just a 3-speed auto. There are NO 5-speed autos that will fit.

 

I suspect you just have the stock 3-speed auto. They don't have overdrive.

 

And revving isn't a problem. This isn't a V-8; you can safely run it at 5K. Top gear in the 3-speed is 1:1, just like the 4-speed manual, and I can run my 4-speed at 70MPH no problem. So unless it's slipping badly, just ignore the noise, because these are LOUD trucks. I can't count how many Datsun truck owners, new and old, think that doing 70 is too fast. It's not. These things redline OVER 7000, with max HP at 5600. On the freeway, at 60MPH with 4.38:1 rears and a 1:1 trans you still aren't hitting 4000.

[chipotle]

The 4-speed auto wasn't stock to begin with. The 4-speed Auto that fits an L-series engine only came in '83-84 Maximas. And even that is not a "bolt in" mod, the transmission is longer and larger than the stock trans.

 

The original was just a 3-speed auto. There are NO 5-speed autos that will fit.

 

I suspect you just have the stock 3-speed auto. They don't have overdrive.

 

And revving isn't a problem. This isn't a V-8; you can safely run it at 5K. Top gear in the 3-speed is 1:1, just like the 4-speed manual, and I can run my 4-speed at 70MPH no problem. So unless it's slipping badly, just ignore the noise, because these are LOUD trucks. I can't count how many Datsun truck owners, new and old, think that doing 70 is too fast. It's not. These things redline OVER 7000, with max HP at 5600. On the freeway, at 60MPH with 4.38:1 rears and a 1:1 trans you still aren't hitting 4000.

 

your right .. my Datsun is still all original so it is a 3speed auto.. (Question for everyone that read's this) tell me what rpm your truck is at when driving exactly 65mph.. mine came with an original owner installed Vintage Mario Andretti Special Edition Tachometer So I will know if im in the clear for commuting..(as I know I will need it to drive in california)

 

[datsunaholic]

Hmm, all my 620s with tachs have 5-speeds so they run around 3000 @ 60. My Mom's '73 OTOH has 4.88:1 rear gears and a 4-speed and turns a little over 4200 at 65.

 

Yours should be a little under 4k @ 65, but since an auto slips it could be more. No lockup converters there.