550 Stiff Shifting When WARM ?

Has oil been changed since this started or did it start after last gear oil change ?
Sounds like an oil issue. Might try different brand.
I have repaired a lot of 550 transmissions and this has not been one of their issues.

 

Products change without notice. Id try something else to see if that is the cause.

 

What oil is being used? I had a similar issue with my 550, oil was changed by one of the most respected independent shops in the mid-Atlantic area just before I purchased the car. I was a bit leery of what was used as they felt the need to add some modifiers. I had another shop change the oil in the tranny and the more I drive it, the easier it is to shift, hot or cold.

 

Mine does the same with fresh oil but only in 2nd gear which feels butter smooth when cold but almost spongy when warm. I have found that going into 2nd gear asap after declutching solves the issue, by not letting engine speed fall. It took a bit of getting used to but with a lightened stock flywheel it makes for sharp and quick gear changes and improve the driving experience dramatically. It seems to me that these synchros just do not like lazy gear changes and all 550s I test drove before purchasing mine felt somewhat similar.

 

All gears the same more or less?

I have seen the shifter shafts internal to the transmission bind in 360 and 430 transmissions but never 550. The shaft in the shift box itself I have seen bind in a lot of Ferraris. Sometimes removal, disassembly and lubrication fixes it and I have had a few where I have had to perform mild machine work to the aluminum bore the shaft rides in.

A shift box issue really doesn't seem like temperature should affect it but internal shaft binding could be.

Cannot picture in my mind right now what the external shift shaft looks like but the stainless exhaust in those expands a lot when it gets good and hot. Tail pipe protrusion is noticeably different cold to hot. Might be sure when it gets hot the pipes cannot possibly foul the rod.

Also in 360 the shift assembly on the side of the trans has a centering detent ball assembly. 550 has a very similar part. Those have been known to fill up with muck from old gear oil and not want to compress. That deserves consideration.

Id consider taking the box off the side, taking it apart and cleaning it all out. Old thick gear oil does collect there.

 

Brian- Is it possible he has too much LSD additive in the gear oil and that is not allowing the synchros to work properly? Too slippery?

 

I suppose its possible. Always hard to judge based on someones description alone. Problem would have had to be repeated at oil changes. Changing oil and leaving it out would tell you. have to drive it 100 or 200 miles to be sure. His problem does fit description of issues I've seen in 360/430. Never 550 but they're getting older and there is always a first time. Maybe just put Mobile 1 gear oil in it.Usually works very well in them.

Maybe I am more tolerant than others but I drive very few Ferraris with no additive that have enough LSD chatter to bother me. I just don't use it in my cars. I ignore the chatter and enjoy the better shifting. Live axle rear ends can be really bad with big long axles that wind up. Ferraris don't have that. My Buick Grand National was really bad.

 

I just read up on MGC additive. They are bragging about characteristics that are contraindicated for use with synchronizers.

Quit using it.

May not fix the problem but for sure it is not the product you want to be using.

 

Just bumping this thread to mention that my shifting issues when hot are now gone after replacing the oil. The Motul Gear 300 LS 75W90 was replaced with Red Line 75W90 NS, often recommended on here. I feel like driving a whole new car.

 

Sounds like an inexpencive way to get a whole new car! I will try it too. My 550 have a few times been a bit hard to get into first from standstill after longer periods of going fast on Autobahn. But not always.

 

I use Ravenol J1C1109 SAE 75W-90 in both my 575M or 512TR. (The 456M has an automatic transaxle...)