jrob
Florence, MS
Deleteorangefj45 said:
JT's FJ40 build
- Thread starter fountainhead
- Start date
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Lookin good
So, I guess the next time I'm under the GunRunner I'll have to Loctite the pan bolts. Can't wait!
- Thread starter
- #124
Oil pan bolts individually removed, cleaned, dabbed with blue locktite, and retorqued in pattern...all while the engine was dangling from the hoist. Sorry, no pictures of that small safety hazard.
Pressure plate bolts taken to 21 lbs.
Tranny hump removed (loudly) by Jrob.
Pressure plate bolts taken to 21 lbs.
Tranny hump removed (loudly) by Jrob.
- Thread starter
- #125
I've read a ton of Saginaw power steering conversion threads, and, in general, there seems to be a lot of confusion around which gear box should be used. For my application (and most others I've seen) the basic requirements are for a 13/16", 36 spline input shaft, a 4 bolt mount, and preferably a 4.25 lock to lock turn. Seems like you could just walk up to the counter at Napa, give them these specs, and walk out with the right box. You cannot.
Based on my research I've concluded the following (if any of this is an over simplification or is blatantly incorrect please correct me):
- There are 2 commonly referenced Saginaw gear boxes: part numbers 27-6529 and 27-6537.
- The 6529 box is typically referred to as the J20 box.
- The 6537 box is typically referred to as the Impala box.
- Both boxes have a 13/16", 36 spline input shaft and have a 4 bolt mount pattern.
- For what it's worth, both boxes name both J20's and various Impala models on their compatibility lists.
- The 6529 has a larger piston, and is theoretically the 'stronger' box.
- The casting numbers on the boxes have nothing to do with how boxes themselves are configured with regards to lock to lock turn specs.
- BOTH boxes have both 3.25 or a 4.25 lock to lock turn flavors.
- Personally, I believe the unicorn box is a 6529 "J20" box with a 4.25 lock to lock turn.
All of that being said I ended up ordering one of each from O'Reilly this week. I've taken some comparison pictures for posterity sake. You can see minor differences in the bodies of the boxes:
Based on my research I've concluded the following (if any of this is an over simplification or is blatantly incorrect please correct me):
- There are 2 commonly referenced Saginaw gear boxes: part numbers 27-6529 and 27-6537.
- The 6529 box is typically referred to as the J20 box.
- The 6537 box is typically referred to as the Impala box.
- Both boxes have a 13/16", 36 spline input shaft and have a 4 bolt mount pattern.
- For what it's worth, both boxes name both J20's and various Impala models on their compatibility lists.
- The 6529 has a larger piston, and is theoretically the 'stronger' box.
- The casting numbers on the boxes have nothing to do with how boxes themselves are configured with regards to lock to lock turn specs.
- BOTH boxes have both 3.25 or a 4.25 lock to lock turn flavors.
- Personally, I believe the unicorn box is a 6529 "J20" box with a 4.25 lock to lock turn.
All of that being said I ended up ordering one of each from O'Reilly this week. I've taken some comparison pictures for posterity sake. You can see minor differences in the bodies of the boxes:
- Thread starter
- #126
Mount side of the 6529 box:
Mount side of the 6537 box (notice how the upper right hand mount point is flush where the 6529 is somewhat recessed...not sure what the implication of that is):
End to end comparison...you can see that the 6529 cylinder is indeed larger:
Bottom:
Mount side of the 6537 box (notice how the upper right hand mount point is flush where the 6529 is somewhat recessed...not sure what the implication of that is):
End to end comparison...you can see that the 6529 cylinder is indeed larger:
Bottom:
- Thread starter
- #127
Random shots of bottom and casting numbers (6529 is on top):
- Thread starter
- #128
After all that, it turns out that my 6529 box has a 3.25 lock to lock turn and my 6537 box has a 4.25 lock to lock turn. The ONE thing I've found to be consistent in all of these Saginaw threads is that no one ever seems to get the exact box they were looking for on the first try. I was looking for the unicorn, but, at this point I think I'll just move out with the 6537 box.
Pictures of it all installed and setup soon I hope.
Pictures of it all installed and setup soon I hope.
orangefj45
Supporting Vendor
I stock the 6529s but it's always a crap shoot. We make sure they're 4.25 turn boxes ......
Are you going with the flaming river shaft and joints?
Are you going with the flaming river shaft and joints?
I got the 3.25. It's a bitch to drive for awhile. I've developed some muscle memory so it's not so bad anymore.
I need to swap it out. Thanks for the write-up.
I need to swap it out. Thanks for the write-up.
Bang Bang
Age is a state of mind.
Nice write-up. Couple of questions for both you guys. What makes it a bitch to drive the 3.25 box? And how do you tell if it's a 3.25 or 4.25 box?
- Thread starter
- #132
I've got the rod kit from Luke...it's got spicer joints.
- Thread starter
- #133
I've never driven a rig with a 3.25 box on it, but. according to numerous threads. 'normal' steering corrections are greatly exaggerated as compared to what you'd be used to.
I vise grips on the input shaft, turned it to lock in one direction, noted the location, then started turning in the other direction until it hit lock again and counted the revolutions.
Uhhh this sounds like gay code or something unholy. Where is charles to define it for us?
I think you mentioned earlier that you may drill & tap it for ram assist...or maybe that was in another thread. Anway. Its a Good time to do it. I ended up just buying a drilled & tap box instead of drilling it myself. I needed a new box any. Plus i don't trust my luck sometimes. If ya ever plan on going with a big tire you may want to atleast have the option. You can always run it with the drill and tapped hole plugged till that day comes.
Just something that i thought of.
Yep. Have it prepped for assist. You will want it.
I got into a big discussion on this once with Lance at PSC and he said it is very common for certain people in the industry to tap the boxes improperly and there is no way to get proper flow through the box.
Also, matching the ram, pump and box are crucial.
To me, this is a place that I was willing to spend extra money after all the headaches overheating p/s caused me in the beginning.
I got into a big discussion on this once with Lance at PSC and he said it is very common for certain people in the industry to tap the boxes improperly and there is no way to get proper flow through the box.
Also, matching the ram, pump and box are crucial.
To me, this is a place that I was willing to spend extra money after all the headaches overheating p/s caused me in the beginning.
- Thread starter
- #136
I looked at the PSC boxes several months ago. All of their boxes are listed as 'variable ratio'. Cross referencing that with info from other sites led me to believe that those were all 3.25 boxes (i.e. all 3.25 boxes were actually variable ratio boxes). Again, that may be an incorrect conclusion, but that's where I landed, and all of that just added to the confusion. So, in looking for this elusive 4.25 box, I moved onto other options.
As part of the shotgun approach due to the recent availability scare, I reached out to another company looking for a ported and tapped box. After an initial response from them the dialog went dark; they might be having trouble sourcing these boxes as well...who knows.
It sounds like the 6529 box is the way to go. I just ordered the last two O'Reilly had in stock. They all have free shipping, and I can return all the ones I don't use at the local store. Hopefully one of the three 6529 boxes I end up with will be a 4.25 box. Otherwise I'll beg Georg to sell me one from his inventory. If they are all spoken for, I'll stick to the original plan and roll out with the 4.25 6537 box that arrived yesterday.
As for porting, I'll just deal with that if/when it becomes an issue. Worst case, I'll remove the box and ship it off to be ported.
As part of the shotgun approach due to the recent availability scare, I reached out to another company looking for a ported and tapped box. After an initial response from them the dialog went dark; they might be having trouble sourcing these boxes as well...who knows.
It sounds like the 6529 box is the way to go. I just ordered the last two O'Reilly had in stock. They all have free shipping, and I can return all the ones I don't use at the local store. Hopefully one of the three 6529 boxes I end up with will be a 4.25 box. Otherwise I'll beg Georg to sell me one from his inventory. If they are all spoken for, I'll stick to the original plan and roll out with the 4.25 6537 box that arrived yesterday.
As for porting, I'll just deal with that if/when it becomes an issue. Worst case, I'll remove the box and ship it off to be ported.
- Thread starter
- #137
And, yes, I will over think ANYTHING. I went down the rabbit hole on the power steering conversion thing (and probably a few other things as well).
Move along...nothing to see here.
Move along...nothing to see here.
Better to overthink than underthink .. As long as overthinking doesn't cause inaction.
Longer way of saying paralysis by analysis.
Longer way of saying paralysis by analysis.
Bomar
SILVER Star
Get it....i like it
admitting to the problem is half the battle. You are my MF HERO.