Help me id trans

[Just Joel]

Bought this with an l20b that formally resided in a 510. I know it’s a long tail five speed but not sure of the model and original application. I need to order new seals and a reverse light sensor. Also, for the sensors I’m not using, can I remove and just plug the holes? They seem to be leaking :blink:

 

 

 

Thanks

Joel

[Sealik]

It looks like this????

 

 

Was out of a 1980 720 2WD L20B

 

The switches can be removed and plugged

[datzenmike]

Bought this with an l20b that formally resided in a 510. I know it’s a long tail five speed but not sure of the model and original application. I need to order new seals and a reverse light sensor. Also, for the sensors I’m not using, can I remove and just plug the holes? They seem to be leaking :blink:

 

 

 

Thanks

Joel

 

It's an FS5W71B 5speed for use with the L series motor. They were introduced for the '77 model year on the 280z and the 620 truck and for the '79 810 and this one appears to be no newer than '79. The clutch slave is for a car but proves nothing really... if it had a truck slave on it, it might add weight to the fact of it being from a truck. The reverse light switch is to the front, the other switch is the top gear or 5th gear switch which I can find no mention of for use with the 280z or first year zx ('79) but the '79 620 truck did use it.

 

If it is still out, place in first and put a mark on the input spline and one on the output spline. I carefully clamp a pair of vice grips to the input spline for turning it. If you measure careful, turn the input spline and count the number of turns to give 10 turns of the output. If close to 36 turns then you have a '79 620 truck 5 speed. If you get 33 times then you have an earlier '77-'78 truck or the 280z 5 speed, they were internally the same.

[Just Joel]

Thanks mike! What can you tell me about the trans as far as strength and reliability? Also, pending a finial id as you described, how is the gearing for a 510 and a spirited driver like myself?

[datzenmike]

Well they were used on the L28 six cylinder and that motor was good for well over 150 hp I believe. Also used on the later 720 with the Z24 motor capable of 130+ ft lbs of torque and the '84-'86 200sx with the CA18ET (turbo) with 130 ? hp. I would say an L20B shouldn't bother it too much.

 

Tips for 5 speed longevity:

 

Change the oil every 30K miles.

Use 80 W 90 GL 4 oil, NOT GL 5

If climbing hills, passing on the highway or carrying heavy loads (towing) shift into and use 4th gear to take the strain off the counter shaft.

[Eagle_Adam]

 

Tips for 5 speed longevity:

 

Change the oil every 30K miles.

Use 80 W 90 GL 4 oil, NOT GL 5

If climbing hills, passing on the highway or carrying heavy loads (towing) shift into and use 4th gear to take the strain off the counter shaft.

 

Good tips!! Thanx mike

 

Joel thanx again for the bumper!!

[Just Joel]

No problem bud... Can't wait to get this thing running so I can crus over and see your progress ;)

 

Later

Joel

[Just Joel]

Well they were used on the L28 six cylinder and that motor was good for well over 150 hp I believe. Also used on the later 720 with the Z24 motor capable of 130+ ft lbs of torque and the '84-'86 200sx with the CA18ET (turbo) with 130 ? hp. I would say an L20B shouldn't bother it too much.

 

Tips for 5 speed longevity:

 

Change the oil every 30K miles.

Use 80 W 90 GL 4 oil, NOT GL 5

If climbing hills, passing on the highway or carrying heavy loads (towing) shift into and use 4th gear to take the strain off the counter shaft.

 

Thanks mike, good info...

 

Later

Joel

[Just Joel]

It's an FS5W71B 5speed for use with the L series motor. They were introduced for the '77 model year on the 280z and the 620 truck and for the '79 810 and this one appears to be no newer than '79. The clutch slave is for a car but proves nothing really... if it had a truck slave on it, it might add weight to the fact of it being from a truck. The reverse light switch is to the front, the other switch is the top gear or 5th gear switch which I can find no mention of for use with the 280z or first year zx ('79) but the '79 620 truck did use it.

 

If it is still out, place in first and put a mark on the input spline and one on the output spline. I carefully clamp a pair of vice grips to the input spline for turning it. If you measure careful, turn the input spline and count the number of turns to give 10 turns of the output. If close to 36 turns then you have a '79 620 truck 5 speed. If you get 33 times then you have an earlier '77-'78 truck or the 280z 5 speed, they were internally the same.

 

36 turns... So it looks like a 79' truck. So what does this tell you about the ratio and how it would pair to a 510? Also, are the seals and revers light switch the same between the early truck/280Z and the later truck transmission?

 

Thank

Joel

[datzenmike]

36 turns means it's a '79 truck. the ratios are:

 

1st.... 3.592 (roughly 3.6 )

2nd... 2.246

3rd.... 1.415

4th.... 1.000

5th.... 0.882

 

This will work just fine in any vehicle but it favors one with a low numerical rear differential. It could be called a 'wide ratio' 5 speed if compared to others. Let me explain. The 620 truck up till the end of '78 used a 4.375 differential and a transmission with a first gear ratio of 3.321. In an attempt to increase fuel mileage on the highway the rear diff ratio was lowered to a 4.11 but this would make starting in first gear with a heavy load more difficult so the transmission ratios were spaced further apart and first raised to 3.592 to compensate. I'm not saying this is no good for your car, it will still work just fine. What you will find is that it will rev faster and need to change into 2nd sooner, perhaps like half way through an intersection from a stop. An earlier 620 or 280z with the 3.321 gears are a 'middle ratio' transmission. (there are 5 speeds with 3.062 first gears and I would call this a 'close ratio' transmission)

 

The wider apart the ratios the easier the take off BUT... (other than 1st maybe) there is a longer rev up period before shifting and a larger RPM drop into the next gear. A close® ratio is very slightly more bother on starts but once rolling has the gears closer together with less RPM drop on shifts. This favors a race car with minimal stops and more gears to choose to keep the RPMs up and making power. Remember... it's all relative. On a light 510 its not a big deal on the street.. If you were racing on the track a close® ratio 5 speed might give you a slight edge.

 

Yes all switches will screw in and work. A reverse switch is a make contact when in reverse. Other switches may be ON and break contact when placed in certain gears. The wiring terminals may change by year. If just using to plug the holes, go ahead.

[Just Joel]

So what's the typical differential gear ratio for a 510 wagon?

 

Thanks

Joel

[albyneau]

36 turns... So it looks like a 79' truck. So what does this tell you about the ratio and how it would pair to a 510? Also, are the seals and revers light switch the same between the early truck/280Z and the later truck transmission?

 

Thank

Joel

 

Pshaw, you don't want that wide ratio~ you want the semi-close ratio like this one!

http://community.rat...__1#entry476637

 

I see a mini swap meet in our future...!

;)

[Just Joel]

Yes I do, but I already have this one and no monies to buy yours ;)