DatDoug Posted April 16, 2010 Report Share Posted April 16, 2010 RickRat has been looking for a solution to his low geared 73 620 rear-end. I have a 79 parts truck & we took the gears out of it thinking they were 4.11. They were not. They were 4.375 I just picked up a couple of PL510 wagon diffs & I always have been curious if they were compatible with the truck ones. After comparing them side by side they look & measure out to be the same. And the Goon gears are 3.88 compared to the truck 4.375's. So we are going to do the swap. WAIT! I decided to do some reading up on the ol Ratsun Forum about it & thanks to the incredible Ratsun nation I found out that the spline gears are dif. Thanks Datzenmike & Mklotz. Oh & thanks SEARCH. So now we just have to swap out the spline gears from the truck rear to the goon rear & bolt her up. Pics to come as well as final verdict :) Quote Link to comment
TrevDaddy Posted April 17, 2010 Report Share Posted April 17, 2010 Awesome. Would this be a logical mod with an LZ22/5spd swap for overall usability? Quote Link to comment
datzenmike Posted April 17, 2010 Report Share Posted April 17, 2010 '79 620 automatics were 4.375. All 4 and 5 speeds were factory 4.11s unless changed, or you have a cab/chassis option. 720 trucks used 3.3645, 3.70, 3.889, 4.11, 4.375, 4.625 depending on year and model. And no side gear swap. Quote Link to comment
datzenmike Posted April 17, 2010 Report Share Posted April 17, 2010 Awesome. Would this be a logical mod with an LZ22/5spd swap for overall usability? Sure, if not likely to be towing and carrying loads often. Quote Link to comment
DatDoug Posted April 17, 2010 Author Report Share Posted April 17, 2010 '79 620 automatics were 4.375. All 4 and 5 speeds were factory 4.11s unless changed, or you have a cab/chassis option. 720 trucks used 3.3645, 3.70, 3.889, 4.11, 4.375, 4.625 depending on year and model. And no side gear swap. This rear dif came out of the same 79 620 that I got my LONGSHAFT Dogled 5speed out of so who knows?? It mite av been an auto truck once. Quote Link to comment
Guest Rick-rat Posted April 17, 2010 Report Share Posted April 17, 2010 Got home, no noises seems to go faster at lower RPM, will know better when I go on the road with the wife to check the speedometer cause hers is right on in her new car. Thanks to dat doug for all of his help today, and I think that rear we took out is not in very good shape, vibration I have had for a while is gone now, will add info tomorrow on the speed and RPM differences Quote Link to comment
Guest Rick-rat Posted April 17, 2010 Report Share Posted April 17, 2010 These 3.88 gears will be perfect for my use, This corrected my speedometer and now what speed it says is the actual speed that I am going. Now I can do75 at just over 4000 RPM, was 65 or 66 at 4000 before with the 4.37 gears, 60 at 3200, 65 at 3500, most of my driving is on the freeway and can now pass a few people and keep up with traffic. I am pleased with the results so far and should have a good increase in mileage. Quote Link to comment
datzenmike Posted April 17, 2010 Report Share Posted April 17, 2010 This rear dif came out of the same 79 620 that I got my LONGSHAFT Dogled 5speed out of so who knows?? It mite av been an auto truck once. Woah woah woah!!! You have a long dogleg? Is this it?? Quote Link to comment
thisismatt Posted April 17, 2010 Report Share Posted April 17, 2010 ahhhhhhhhhhhhhhhhh, levitating doglegs scare me :( Quote Link to comment
DatDoug Posted April 18, 2010 Author Report Share Posted April 18, 2010 Woah woah woah!!! You have a long dogleg? Is this it?? I dont know if that is the exact 1 but it did look similar. What the hell did those come in? Quote Link to comment
motavated Posted April 18, 2010 Report Share Posted April 18, 2010 Are they rare? I dont get it... Explains! Quote Link to comment
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