Best easy to find tranny for my L20

[kgrantkey]

Looks like i gotta replace the rear main seal in my 620 lil'hustler w/L20 and 4speed tranny.   The engine I'll keep til i die. the tranny is a good 4 speed. Will do nothing but replace the rear bearing unless i can find a 5 speed that let me go 80-90 mph with less rpm.  I'm clueless about tyranny's that can bolt to an L series motor.  I know the 200sx had a 5 speed. Heck I sold 1 years ago.

 

 Should I just be satisfied with 80 mph on a 4 speed? All I gotta do is replace the rear main. I'll do more if it's beneficial, but I've got a pretty good combination with the L20b/4speed tranny as it is. I just could kick myself for letting the rear main dry out - I didn't drive this truck for several years and feel that's why the rear seal's leaking.

 

I'm not lazy.  I've learned a ton and made many mods from this site. A link or 2 on transmissions that bolt to an L block that are around? Change the bellhousing?  Not ready to start a time consuming project. It'd be great if there was a good 5/6 speed manual tranny that would bolt up from a 300z .

 

BIG THANKS  -  to datzenmike  for retrieving my old username.   I'd breech the subject of photofukit and lost memories but it hurts too much rite now! 

 

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TLDR - is it worth looking for a better tranny than my 4spd to install on my L20b just cause i gotta replace a leaking main seal?

 

 

[datzenmike]

Your profile says S10 and 620 so is that an S10 200sx? or a chevy truck? and what year 620? (it may be in a previous post but I can't be bothered and I don't remember) because this all factors into what 4 or 5 speeds you can use.

 

Rear main seal? Not the engine? you mean the rear seal on the transmission that the driveshaft fits into?

 

 

Lets cut to the probable chase. If it's the transmission seal then fix it. Faster easier and cheaper than another unknown transmission. They are less than $5.

A four speed is fine at any RPM the engine can attain. If this is a '74 or newer the transmission is from a six cylinder car and more than strong enough for an L20B.

[kgrantkey]

I only speak of my datsun 620 truck on this forum. L20b /w 4spd manual.  The rear main seal is the one at the back of the engine that surrounds the crankshaft. I'll probably just change the rear seal, but it's not too hard to jerk the engine and tranny out as 1 with my big ass engine hoist. I'd spend a dollar or two on a 5 speed tranny if it fit to my l20b and the shifter came up thru the floor like it should.

  Honestly, I just told my grandson he could help with the repair cause he luvs this truck. ..and it is leaking oil at the back of the engine.

 

Quote

S10 200sx? or a chevy truck?

- I have an old 1998 S10 chevy truck. 

Edited April 1, 2021 by kgrantkey

[datzenmike]

What year because there were two different lengths used on the 620. Unless you don't mind altering the driveshaft length.

[kgrantkey]

The 4 speed came in one of my pre 1979 datsun trucks. If my memory is correct the 4spd i have is a better model than the 4 spd i thru away. I know there waqs a reason i kept one over the other.

 

...but it's midnight here and i'm gonna lay down.

 

Thanks again for retrieving my username. I'll try to get the list of vehicles and shit straight pretty soon.

[kgrantkey]

OK. that probably settles it. Not gonna change driveshfts. I'll keep the 4 speed. I do catch myself once in a while going for 5th.  Don't drive it much but starting to clean out my junk and alot of it bolts on this truck. 1978 yellow 620 w/4spd manual.

Edited April 1, 2021 by kgrantkey

[kgrantkey]

Still driving my lil'hustler on occasion. It still has a small leak when the engine is running close to the area where the tranny and engine connect.  If I had cranked it every few months I don't think it would be dripping fluid, but let it sit far to long without cranking or driving it.

 

 Gonna drive it to a small business near my house to empty the trash out of the bed.  I promise one day I'll spend a month or two putting this truck back into shape. I have mad the decision I'll have it til I die or forget i'ts mine.

 

Thanks for this site.  May be one of the oldest forums I've ever belonged to, and without a doubt the most informative on the Datsun's.

Edited June 26, 2021 by kgrantkey

[banzai510(hainz)]

I just fill it up every 3 months on my 521 I did 2 rear seals and still leaks 1 front seal. I give up. im getting lazy as I get older.

drive under 60 and call it good

park in gravel

[kgrantkey]

 I was reading on another forum about a guy that had small oil leak on his rear main seal.  Said it was caused due to blow by creating too much pressure in the crankcase with faulty venting.  My leak has gotten better now that i crank it more often.

[datzenmike]

There is a huge block vent on the driver's side going to the PCV valve. There is a folded mesh like fly screen. Very unlikely it would plug, I mean if it did you have worse problems. The valve cover also is open at the top with a hose to the air filter. These two openings should never be messed with or modified, no good will come of it.

 

Keep the PCV valve operational. Single-handedly they double your engine's life, benign in operation, low to no maintenance. Catch cans??? just who are you kidding that you have a 'race car' and need one? The stock PCV set up takes care of any expelled gas and water vapors automatically. Why save it and then have to get rid of it???? They are to collect expelled liquids from a racing engine to keep off the track. How does that apply to the street??? 

[kgrantkey]

Quote

The valve cover also is open at the top with a hose to the air filter. These two openings should never be messed with or modified, no good will come of it.

 

 Good advice.

 

That is what caused my leak. I put the PVC hose that goes to the air filter to the hose on the the drivers side of the engine block. Hard to describe but it put the pressurefrom my lower engine to the valve cover.  It only leaked when running and has stopped now that I corrected it.