620 rear end gears?

[thrillride620]

What rear end gears would a 74 620 w a4 speed have?

[yello620]

Should be 4.375.

[Bleach]

All Datsun 620 Gear Ratios

 

ok, just a little something I threw together. :D :eek:

[RacnJsn95]

That's awesome bleach! Now I'll never have to ask again! ;)

[nismopu]

this should probly be a sticky in the trucks section.

[69FJWagon]

hmm I have a 1972.5 620 and I checked the rear gear ratio and its a 4:37 gear and I bought it from the original owner and it was more than stock...wonder if it was an option?

[datzenmike]

Hmmm, ? I get 4.375 standard for all US 620s until '79 then 4.11s.

 

The 521s were 4.375 as well, except for the J15? OHV engines, that had 4.875s.

[Bleach]

I used to have that page on my old website. When I switched over to my domain "BleachGarage.com" I never put it back. I intend to have it available on line from my main page... funny how it really only took me a second to copy that up.

 

anyway... I might add some of the 521 and 720 gear ratios too since they are all H190 (for the most part) so it gives people a more complete compatibility list. :D

I'll check with Datsunaholic on that and try to pull all info from Factory Nissan Manuals and not just hearsay

[OL YELLER]

hmm I have a 1972.5 620 and I checked the rear gear ratio and its a 4:37 gear and I bought it from the original owner and it was more than stock...wonder if it was an option?

 

I also have a 72.5 bought from the original owner.....what is your vin number and the date of Manufacture?......mine is 029252 Mfg date 4/72

[datzenmike]

I used to have that page on my old website. When I switched over to my domain "BleachGarage.com" I never put it back. I intend to have it available on line from my main page... funny how it really only took me a second to copy that up.

 

anyway... I might add some of the 521 and 720 gear ratios too since they are all H190 (for the most part) so it gives people a more complete compatibility list. :D

I'll check with Datsunaholic on that and try to pull all info from Factory Nissan Manuals and not just hearsay

 

A most excellent idea Bleach, specially the 720s as they had many other gear options.

[Bleach]

hmm I have a 1972.5 620 and I checked the rear gear ratio and its a 4:37 gear and I bought it from the original owner and it was more than stock...wonder if it was an option?

 

I got my info out of the Factory Service Manuals. There were no other options than those listed. But, I don't have a 1972 Datsun 620 manual. (if those even exist) Since yours is such an early 620 maybe it carried over the 4.375 rear from the 1972 521 trucks.

[OL YELLER]

I got my info out of the Factory Service Manuals. There were no other options than those listed. But, I don't have a 1972 Datsun 620 manual. (if those even exist) Since yours is such an early 620 maybe it carried over the 4.375 rear from the 1972 521 trucks.

 

Here ya go guys..straight out of the 1972 Service Manual.....looks like 4.375 be the right one...

[69FJWagon]

I also have a 72.5 bought from the original owner.....what is your vin number and the date of Manufacture?......mine is 029252 Mfg date 4/72

 

i cant remember my vin but know the production date is 5/1972 so yours is a month older haha thats cool I thought it was cool that its a early 620, my 510 wagon is a 69 but it was first sold in 70 kinda sucks my reg says 1970 for awile I had my wagon 1969, roadster 1970, 2door 510 1971, and my other 2 door 510 1972 :D

[Z-train]

WHo here has gone from a 4.37 to a 4.10?What differences were found?Thanks.

[]2eDeYe]

More top end speed, less power off the line.

Haven't done it, but that's what the difference will be...and it won't be a whole lot of difference, but it should be barely noticable.

[datsunaholic]

Look at the bottom table of this text file. It gives the engine RPMs at a given speed (60MPH) with a given tire size. Changing the tire size or speed would alter the numbers, but it's a starting point to see the difference. It's not drastic.

 

http://64.125.210.117/datsun/gearratios.txt

[Z-train]

O.K.-i deserved those answers.:blink:Actually,what i meant was with the drop to 4.10 was there a decernable MPG increase?Was there a noticable change in low end grunt that made you wish you hadn't done the swap?

[OL YELLER]

O.K.-i deserved those answers.:blink:Actually,what i meant was with the drop to 4.10 was there a decernable MPG increase?Was there a noticable change in low end grunt that made you wish you hadn't done the swap?

 

Your last line concerning the low end grunt and that "wish i hadn't...." well Ray (my Son "Rays 74") and I both had our rear ends switched to 89 hardbody rear end gears...now has 3:73s and really very little low end grunt...BUT...the 60 mph rpm are quite a bit different...whereas before..with the 4.375 the motor was crankin at well over 4000...now with the newer gears 60 mph rpms are right at 2800!!!!!...I s'pose I am more than willin to give up the grunt for the lower revs at speed .......................long winded way of sayin I like the swap...

[OL YELLER]

Doug, lookin at the chart you posted it said that I should have seen approx 3500 at 60 mph with my 73 and the 4 speed...but, I do remember my rpms in the 4 grand range..wonder why that would have been...I am using that size tire by the way...anyway, and however..my own experience was so dramatic to be unbelievable...sort of LOL.....

[yello620]

I had a 4.10 gear change from a 79 620 for a little while(carrier center pin went bad). Wish i still had them too, had to put the 4.37 rear back in. But, while the 4.10's were installed, I didn't notice any difference in power leaving a stoplight or sign. Actually found it to be smoother taking off cause i could drive more than 20 feet before needing to shift. At freeway speeds it was very noticable in the noise of the engine RPM's, however i didn't notice any gain in MPG. But didn't lose MPG either.

 

With the 4.37's, I find myself starting out in 2nd gear very often. Just not even using first. And I am one of those driver's that has to be the first one up to speed after leaving a stoplight.

 

When I go looking for another rear for my truck i will be looking for a 3.90 rear gear. That should give me a noticable difference in first gear, and on the highway.

 

Hope this helps the FAQ

Jason

[OL YELLER]

That is what I forgot to mention with the 4.37 gears...for those of you who have ridden early dirt bikes...the deal with the early datsun gears was the same as an early Honda Elsinore 125..usually shifting into 3rd gear by the time you get to the other side of the intersextion..HA HA Ha..I mean like bang..bang..bang...shift way too fast.................

[datsunaholic]

I have a tach in my Mom's '73... it's around 3900 at 60. My mom's '73 has the 4.88s in it, which lines up with the chart.

[dat521gatherer]

yep both my 521's are about 4000rpm on the freeway. great info bleach and datsunaholic.

[Z-train]

Cool.I SUSPECTED a few of the answers.Does Datsun ID the gear ratio on the housing?

[datzenmike]

WHo here has gone from a 4.37 to a 4.10?What differences were found?Thanks.

 

411s from an '82 auto into my '78. As long as you are at stock weight 2wd it makes driving around town easier. Less shifting but less take off torque too. If you plan to be using for work or carry weight around on a regular basis I would say no.

 

My truck now weighs 3,400 with 12.5X31s, s-l-o-w take offs and struggle on hills. The 4.375 blew and I had the spare almost in before checking the ratio, it was too late to do anything about it.