Posted by Tom Nyren
It's always fun to talk with people who actually work on Ferraris. I have undertaken a task which most people have said is impossible and that is to rebuild the rear load leveling shocks on my 365. After disassembling them (with much caution) they appear to be in excellent shape inside except the shaft seal which had turned to dust. I have found all the pieces to reassemble them and one is completely assembled. Because they leaked, I do not know how much fluid they take or what weight the oil should be. Also how much pressure there should be inside. I have an idea where the oil and gas go but am not positive as they are fairly complex. I have made a tool to repressureize the shock but when disassembling the second shock I found pressure where I thought there should be none. Was this possibly from an internal leak? I have more questions but was wondering if anyone else has done this or knows a place to have this done. Koni will barely admit they had anything to do with these and does not rebuild them. Thanks, Tom
365 GT 2+2 rear load leveling shocks
Re: 365 GT 2+2 rear load leveling shocks
Posted by Dr. Ian Levy
Hi Tom
I have tried to get my sefl-levellers for a 365 GTC4 repaired / serviced wuthout success. I don't know if they are the same on a 365GT 2+2.
I sent mine back to Koni in Holland who sent them straight back without touching them.
They appear to be irreplaceable & unserviceable.
Hi Tom
I have tried to get my sefl-levellers for a 365 GTC4 repaired / serviced wuthout success. I don't know if they are the same on a 365GT 2+2.
I sent mine back to Koni in Holland who sent them straight back without touching them.
They appear to be irreplaceable & unserviceable.
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom
Hi Dr. Levy, I think they are basically the same for different models and you are correct about Koni and availability. I have found NOS (new old stock) for about $1500 each but I would be a little nervous buying 30 year old parts. These have a rubber bladder inside and if not stored compressed, the bladder is folded over on itself with about 350PSI pushing on it and will eventually cause a crease which could fail under use. The seals could also go bad and you are back where you started. For anyone storing a car with these on them they should make sure the shafts do not rust and that they are not extended (ie: chassis on jackstands, wheels hanging free). If removed from vehicle, they should (carefully) be compressed to ride height length and cabled through ends for storage. I say carefully because they take about 350lbs to compress. I have temporarily converted to Aldan coil over shocks until I can fix mine (if possible). I have heard of some people interchanging the self leveling shocks between different models. The difference is probably the internal pressure for the slight difference in vehicle weight.  
Hi Dr. Levy, I think they are basically the same for different models and you are correct about Koni and availability. I have found NOS (new old stock) for about $1500 each but I would be a little nervous buying 30 year old parts. These have a rubber bladder inside and if not stored compressed, the bladder is folded over on itself with about 350PSI pushing on it and will eventually cause a crease which could fail under use. The seals could also go bad and you are back where you started. For anyone storing a car with these on them they should make sure the shafts do not rust and that they are not extended (ie: chassis on jackstands, wheels hanging free). If removed from vehicle, they should (carefully) be compressed to ride height length and cabled through ends for storage. I say carefully because they take about 350lbs to compress. I have temporarily converted to Aldan coil over shocks until I can fix mine (if possible). I have heard of some people interchanging the self leveling shocks between different models. The difference is probably the internal pressure for the slight difference in vehicle weight.  
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom Yang
I believe there is a supplier in Arizona USA that rebuilds these shocks. Hopefully some one reading along will chime in on their contact information, as I've misplaced it!
Tom Yang
I believe there is a supplier in Arizona USA that rebuilds these shocks. Hopefully some one reading along will chime in on their contact information, as I've misplaced it!
Tom Yang
Re: 365 GT 2+2 rear load leveling shocks
Posted by levy@btopenworld.com">Dr. Ian Levy
Hi Tom
Thanks for your info & I will do as you suggeast.
Mine have been off the car for a while & I have no idea what length they should be compressed to.
Would anyone with a GTC 4 be so kind at to measure the distance between the top & bottom mounts a let me know.
Thanks again
Ian  
Hi Tom
Thanks for your info & I will do as you suggeast.
Mine have been off the car for a while & I have no idea what length they should be compressed to.
Would anyone with a GTC 4 be so kind at to measure the distance between the top & bottom mounts a let me know.
Thanks again
Ian  
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom
O.K. Guys here's the information:
Jeff LeBlond
22045 N. 88th Avee
Peoria, AZ 85383
623-566-1628
Koni recommends this guy that may be able to help you rebuild the self leveling koni shocks.
Good luck, and let me know what you find.
Tom
O.K. Guys here's the information:
Jeff LeBlond
22045 N. 88th Avee
Peoria, AZ 85383
623-566-1628
Koni recommends this guy that may be able to help you rebuild the self leveling koni shocks.
Good luck, and let me know what you find.
Tom
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom Nyren
Hi Dr. Levy, I don't think the length is critical, just about 1/2 way compressed. I tried anothet option on my car which did not work. The Koni design is licenced from Nivomat (Boge) who makes a very similiar shock for Volvos. I modified a set (end bushing width and hole size) but they were about 50lbs low on lift per side for my car. They could possibly work on your car as it weighs about 350lbs less than mine. It does stray away from orginality but they are made with the latest design and materials and are NEW. If you are interested, I could ship you mine, otherwise I am going to return the bushings to original and sell them to some Volvo owner. They retail for $400+ each, I paid about $465 for the pair. I would sell the modified pair for $400. It would be interesting just to see if they would work on the lighter cars as the modifications are fairly easy. I did not drive my car with them on it as it was not running at the time so I do not know if they would of pumped up to the proper height. However testing them for load with a scale and compressor against the Konis they had about 50lbs less lift. I will check out Tom's recomendation also. Thanks, Tom
Hi Dr. Levy, I don't think the length is critical, just about 1/2 way compressed. I tried anothet option on my car which did not work. The Koni design is licenced from Nivomat (Boge) who makes a very similiar shock for Volvos. I modified a set (end bushing width and hole size) but they were about 50lbs low on lift per side for my car. They could possibly work on your car as it weighs about 350lbs less than mine. It does stray away from orginality but they are made with the latest design and materials and are NEW. If you are interested, I could ship you mine, otherwise I am going to return the bushings to original and sell them to some Volvo owner. They retail for $400+ each, I paid about $465 for the pair. I would sell the modified pair for $400. It would be interesting just to see if they would work on the lighter cars as the modifications are fairly easy. I did not drive my car with them on it as it was not running at the time so I do not know if they would of pumped up to the proper height. However testing them for load with a scale and compressor against the Konis they had about 50lbs less lift. I will check out Tom's recomendation also. Thanks, Tom
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom Yang
Hi Tom (Nyren),
There were a bunch of redundant posts to the message board, so I deleted them. Ian seemed to have the same problem this morning. Is there something wrong with my server, or are you guys accidentally submitting the same messages? I always want to make sure this site is working properly!
Tom Yang
Hi Tom (Nyren),
There were a bunch of redundant posts to the message board, so I deleted them. Ian seemed to have the same problem this morning. Is there something wrong with my server, or are you guys accidentally submitting the same messages? I always want to make sure this site is working properly!
Tom Yang
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom N.
Tom, I got a message that there was something wrong with the server so I re-sent it a few times to see if it would work. I didn't realize it was posting until I checked it. Tom N
Tom, I got a message that there was something wrong with the server so I re-sent it a few times to see if it would work. I didn't realize it was posting until I checked it. Tom N
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom Yang
No problem. It's as easy as hitting the "delete" for me! I'm just making sure it's a usable bullitin board for Ferrari issues!
Tom
No problem. It's as easy as hitting the "delete" for me! I'm just making sure it's a usable bullitin board for Ferrari issues!
Tom
Re: 365 GT 2+2 rear load leveling shocks
Posted by Les
A few months ago I went searching through both Koni's and Ferrari's older tech material and I found the same part numbers and rates being used from 365GT2+2 through 400 (non-injected). The "regular" coil-overs were different.
Les
365GTC/4
A few months ago I went searching through both Koni's and Ferrari's older tech material and I found the same part numbers and rates being used from 365GT2+2 through 400 (non-injected). The "regular" coil-overs were different.
Les
365GTC/4
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom N
I called Jeff and had a great conversation. He does repair the load levelers at a very reasonable price which is based on how much you want done and how bad they are. He will take them apart (usually at no charge) to give an appraisal of condition and cost. I am going to send him mine and will give an update when I get them back. Thanks!
I called Jeff and had a great conversation. He does repair the load levelers at a very reasonable price which is based on how much you want done and how bad they are. He will take them apart (usually at no charge) to give an appraisal of condition and cost. I am going to send him mine and will give an update when I get them back. Thanks!
Re: 365 GT 2+2 rear load leveling shocks
Posted by tom yang
Hi Tom N!
That's good enough news to post this contact in the suppliers page. Let me know what this rebuild turns out so we can help others with the same problem.
Tom
Hi Tom N!
That's good enough news to post this contact in the suppliers page. Let me know what this rebuild turns out so we can help others with the same problem.
Tom
Re: 365 GT 2+2 rear load leveling shocks
Posted by Aaron Masters
I have a C4 with leaking/non-usable levelers. I will tell you what I have done and what I know/believe.
First- I replaced the levelers with air shocks as a stopgap. They work, but they also have damping and so the ride is a little stiffer than the levelers provided. I do not believe that the levelers provide any damping.
I have been casually looking for spring over shock that have low damping values. I figured if I took the oil out of the air-shocks, they would eventually seize.
I was unable to find anyone on the planet that would rebuild the levelers for me, so being an engineer, I did the engineering thing – I took one apart.
My observation, the leveler is a air/gas/(probably nitrogen) air bag with a series fluid/oil ratchet. Which means that oil is passed from the behind “the piston” to in front of the piston through a check valve until the ride height is reached. At the point of correct ride height, a valve opens and any excess oil is allowed to leak back to the “behind the piston” cavity.
There is a “gas cavity” between the outer case and a rubber/flexible bladder. It is accessed by a socket head screw on the side. The upper oil (in front of the piston) cavity is accessed by a screw on the top and the “behind the piston” cavity is accessed by the lower side screw.
Based on the piston diameter and the pressure on the leveler, I would estimate the gas pressure to be between 350 and 400 lbs/sq.in.
The failures in my levelers are at the shaft seals, probably like everyone else’s. I have found a number of seal manufactures but have not yet done the homework to figure out what I can make-work.
I will repost if I get a chance to work on this further. Comments or corrections are certainly welcome. I understand there are “a bunch of us” with this problem.
Thanks
Aaron
I have a C4 with leaking/non-usable levelers. I will tell you what I have done and what I know/believe.
First- I replaced the levelers with air shocks as a stopgap. They work, but they also have damping and so the ride is a little stiffer than the levelers provided. I do not believe that the levelers provide any damping.
I have been casually looking for spring over shock that have low damping values. I figured if I took the oil out of the air-shocks, they would eventually seize.
I was unable to find anyone on the planet that would rebuild the levelers for me, so being an engineer, I did the engineering thing – I took one apart.
My observation, the leveler is a air/gas/(probably nitrogen) air bag with a series fluid/oil ratchet. Which means that oil is passed from the behind “the piston” to in front of the piston through a check valve until the ride height is reached. At the point of correct ride height, a valve opens and any excess oil is allowed to leak back to the “behind the piston” cavity.
There is a “gas cavity” between the outer case and a rubber/flexible bladder. It is accessed by a socket head screw on the side. The upper oil (in front of the piston) cavity is accessed by a screw on the top and the “behind the piston” cavity is accessed by the lower side screw.
Based on the piston diameter and the pressure on the leveler, I would estimate the gas pressure to be between 350 and 400 lbs/sq.in.
The failures in my levelers are at the shaft seals, probably like everyone else’s. I have found a number of seal manufactures but have not yet done the homework to figure out what I can make-work.
I will repost if I get a chance to work on this further. Comments or corrections are certainly welcome. I understand there are “a bunch of us” with this problem.
Thanks
Aaron
Re: 365 GT 2+2 rear load leveling shocks
Posted by Tom
Hi Aaron,
Thanks for the info. If you happen to have pictures, maybe we can put together a "tech tip" on these shocks. That way what you write can live in a more permanent place on this site for other "self leveler" owners.
Tom  
Hi Aaron,
Thanks for the info. If you happen to have pictures, maybe we can put together a "tech tip" on these shocks. That way what you write can live in a more permanent place on this site for other "self leveler" owners.
Tom