Converted my 66 ps gear box to a 12.7:1 ratio with more effort for $75.
jim larson said
Jan 3, 2013
As some of you may know, I've been exploring the possibility of trying to change the ratio and effort of my 66 ps gear box while maintaing the original box and appearance. Here is what I did. I found a box out of a JGC for $35 and a coupling out of a 78 chevy truck with ps for $10. I put the input shaft, worn gear, pistion, etc in the 66 gear box. I reused the 66 pithman shaft and cover ( 66 cover and JCG cover would not work together; however I could have modified the underside of the 66 cover a bit to make it work with the 97 JGC pitman shaft.
I got both a gear rebuild kit for a 97 JGC box and a pitman shaft seal kit for a 66 chevy from Rock Auto with shipping for $28. I transfered bolts from my old 66 coupler to the 78 coupler. The only physical difference is that if you look real close, you might be able to see the input shaft is 3/4" instead of 13"16".
I did not have to change hoses or use inserts as I am using my 66 box.
You're going to love that setup! I hated the steering feel in Jenna's wagon... had the parts to do the swap, but never got around to it.
Bowtieman427 said
Jan 3, 2013
Jim, that is awsome !!!!!!!!
Bungy L-76 said
Jan 23, 2013
What years of the Grand Cherokee will work for this swap? Does it matter if they're 2wd or 4wd?
jim larson said
Jan 23, 2013
I am in FL now, I have a list of the years and codes that have the correct rotation of 86 degrees with the 12.7:1 turn ratio. Remind me in about 3 weeks, as that is when I'll be back in MN.
You need metric adapters from Lee Mfg and a Chevy truck (80s 2wd) ragjoint, or if you are more adventurous like Jim, you can take the boxes apart and swap the internals.
9C1 (police package) Caprices use the same box as the JGC. There may be a minor difference in valving, but the ratio is the same.
SteveS said
Jan 24, 2013
Like Derek said, if your not worried about correct casting you can bolt the whole jeep box in rather than swap internals. I used a Jeep box with the Lee adapters in mine a few years ago, it made a huge difference in handling.
Bowtieman427 said
Jan 25, 2013
Steve when you did this did you have to run diffrent hyd hoses and did it bolt right in with no issues to 72 Chevelle ? Curious if this would solve the NO feedback feel for the road or track I get with the car. I will hopefully get to doing some front end work this year. Since I will have a lot a part up there this may be a good time to get this done too. My kitchen is killing me seems like no time to do any car stuff right now : ( i
Derek69SS said
Jan 25, 2013
You use the stock Chevelle hoses with the Lee Mfg. metric adapters.
Late model engine don't require adapters as we can just use off-the-shelf hoses with metric ends for our late-model PS pumps.
jim larson said
Jan 25, 2013
I think the 76-79 Chevy truck coupler will also work. Either 2 or 4 wheel drive with PS. But as Derek said, only 2 wheel drive with PS from 80-86.
-- Edited by jim larson on Friday 25th of January 2013 08:39:29 AM
SteveS said
Jan 25, 2013
The Lee adapters are basically two bushings that drop in the holes to change the flare of the fitting to the standard Chevelle type. You can see them installed here:
Like Derek said with the modern motor should match the jeep box, but when I put the LS1 in the Lee fittings had pressed themselves in so hard I couldn't get them out. So I have a custom hose that is Old Chevy on the gear side and LS1 on the pump side.
dashboard said
Jan 25, 2013
I’ve followed this post with interest. I changed the gearbox in the Elky going from 4 turns lock to lock to 2.5 turns lock to lock and have been pleased with the results. Does the Jeep gear box offer something more than just the reduction in wheel rotation from lock to lock?
I’m interested in improving the yellow cars handling.
67ss said
Jan 25, 2013
Auto city classics has those bushings. When I was trying to figure out the power steering leaks on the 55 they sent some with my buddy to make sure they were in the pump and power steering box.
Derek69SS said
Jan 25, 2013
Kevin, the JGC box also has a firmer feel to it and better road feedback. You'll like it, even if you don't change anything else.
SteveS said
Jan 25, 2013
It might be cheaper if you can find the bushing from Auto City Classics or someone locally. It's been a few years since I bought mine from Lee Mfg, but I think it came with a rag joint too.
Bowtieman427 said
Jan 26, 2013
thanks I will check out Lee's and Auto City Classics.
jim larson said
Jan 26, 2013
You probably want to rebuild the Jeep box, why not just put the parts in you original chevelle box with a rebuild, no hose or insert issues. Does your 72 box have the 13/16" input shaft or the 3/4". They changed from the 13/16 to the 3/4 sometime in the 70's. If so, you might have the correct coupler. You can probably find a coupler in Oronco, Byron, or Rochester when looking for a JGC box.
Chris R said
Jan 26, 2013
I think Lares up in Cambridge has those fittings as well.
dashboard said
Jan 27, 2013
Is Lares the outfit that rebuilds power steering units?
bowtie said
Jan 27, 2013
yes.
Bowtieman427 said
Feb 2, 2013
Found a box for a good price not 100% sure of fitment Cardone Industries Part Number 27-7525 Steering Gear Notes: Gear Pitman Shaft Spline Counts--3/4 Number Steering Gear Box Turns--3 1/16 - 3 3/8 PS Gear Box Line Thread Size--M18x1.5; M16x1.5 Steering Gear Box Input Shaft Diameter--1.25 Steering Gear Box Output Shaft Diameter--3 It is a remanufactured
Any help on wheather this looks correct please lmk I ask as it states it fits 93, 94, 95 JGC but NOT 96,97, or 98 JGC Any help here would be great thanks in advance.
jim larson said
Apr 4, 2013
WELL I COULDN'T RESIST STARTING THE CAR TODAY TO SEE IN MY PS PROJECT WORKED. WELL IT SEEMS TO WORK FINE.
SO JUST TO RECAP, I PUT THE INTERNALS OF A 97 JEEP GC GEAR BOX INTO A 66 GEAR BOX WITH THE 66 PITMAN SHAFT AND EVERYTHING SEEMS TO WORK. NOW I THINK I SHOULD GET THE FRONT END RE-ALLIGNED.
NOW WE NEED SOME WARM RAIN THE WASH THE ROADS OF THE SALT AND 50+ DEGREE WEATHER.
-- Edited by jim larson on Thursday 4th of April 2013 04:41:54 PM
As some of you may know, I've been exploring the possibility of trying to change the ratio and effort of my 66 ps gear box while maintaing the original box and appearance. Here is what I did. I found a box out of a JGC for $35 and a coupling out of a 78 chevy truck with ps for $10. I put the input shaft, worn gear, pistion, etc in the 66 gear box. I reused the 66 pithman shaft and cover ( 66 cover and JCG cover would not work together; however I could have modified the underside of the 66 cover a bit to make it work with the 97 JGC pitman shaft.
I got both a gear rebuild kit for a 97 JGC box and a pitman shaft seal kit for a 66 chevy from Rock Auto with shipping for $28. I transfered bolts from my old 66 coupler to the 78 coupler. The only physical difference is that if you look real close, you might be able to see the input shaft is 3/4" instead of 13"16".
I did not have to change hoses or use inserts as I am using my 66 box.
What years of the Grand Cherokee will work for this swap? Does it matter if they're 2wd or 4wd?
93-98 GRAND Cherokee
http://www.chevelles.com/forums/showthread.php?t=334534
You need metric adapters from Lee Mfg and a Chevy truck (80s 2wd) ragjoint, or if you are more adventurous like Jim, you can take the boxes apart and swap the internals.
9C1 (police package) Caprices use the same box as the JGC. There may be a minor difference in valving, but the ratio is the same.
Like Derek said, if your not worried about correct casting you can bolt the whole jeep box in rather than swap internals. I used a Jeep box with the Lee adapters in mine a few years ago, it made a huge difference in handling.
Late model engine don't require adapters as we can just use off-the-shelf hoses with metric ends for our late-model PS pumps.
the other type a fittings that just connect the metric fitting on the gear to the hose thread, I think summit sells them.
Something like this: http://www.summitracing.com/parts/ear-991955erl
or thisjavascript:mctmp(0);
-- Edited by jim larson on Friday 25th of January 2013 08:39:29 AM
The Lee adapters are basically two bushings that drop in the holes to change the flare of the fitting to the standard Chevelle type. You can see them installed here:
Like Derek said with the modern motor should match the jeep box, but when I put the LS1 in the Lee fittings had pressed themselves in so hard I couldn't get them out. So I have a custom hose that is Old Chevy on the gear side and LS1 on the pump side.
I’m interested in improving the yellow cars handling.
Auto city classics has those bushings. When I was trying to figure out the power steering leaks on the 55 they sent some with my buddy to make sure they were in the pump and power steering box.
It might be cheaper if you can find the bushing from Auto City Classics or someone locally. It's been a few years since I bought mine from Lee Mfg, but I think it came with a rag joint too.
You probably want to rebuild the Jeep box, why not just put the parts in you original chevelle box with a rebuild, no hose or insert issues. Does your 72 box have the 13/16" input shaft or the 3/4". They changed from the 13/16 to the 3/4 sometime in the 70's. If so, you might have the correct coupler. You can probably find a coupler in Oronco, Byron, or Rochester when looking for a JGC box.
I think Lares up in Cambridge has those fittings as well.
Cardone Industries Part Number 27-7525
Steering Gear
Notes: Gear Pitman Shaft Spline Counts--3/4
Number Steering Gear Box Turns--3 1/16 - 3 3/8
PS Gear Box Line Thread Size--M18x1.5; M16x1.5
Steering Gear Box Input Shaft Diameter--1.25
Steering Gear Box Output Shaft Diameter--3
It is a remanufactured
Any help on wheather this looks correct please lmk
I ask as it states it fits 93, 94, 95 JGC but NOT 96,97, or 98 JGC
Any help here would be great thanks in advance.
WELL I COULDN'T RESIST STARTING THE CAR TODAY TO SEE IN MY PS PROJECT WORKED. WELL IT SEEMS TO WORK FINE.
SO JUST TO RECAP, I PUT THE INTERNALS OF A 97 JEEP GC GEAR BOX INTO A 66 GEAR BOX WITH THE 66 PITMAN SHAFT AND EVERYTHING SEEMS TO WORK. NOW I THINK I SHOULD GET THE FRONT END RE-ALLIGNED.
NOW WE NEED SOME WARM RAIN THE WASH THE ROADS OF THE SALT AND 50+ DEGREE WEATHER.
-- Edited by jim larson on Thursday 4th of April 2013 04:41:54 PM