We rarely have to repair rear axles and usually just clean and inspect the bearings and install new oil seals. Be it a Jaguar, Chevrolet or Alfa Romeo, it is rare that we see a ring and pinion that is damaged or bearings that are worn out. I hate to disturb the factory relationship between the ring and pinion gears so if the bearings check out ok, I keep the thing together.

Additionally, most car companies have figured out how to make the final drive robust and problem free because they are aware of the forces involved with the ring and pinion bevel gears – except for Ferrari. They used a deep groove ball bearing and sliding inner race roller bearing that cannot handle the axial loads on the pinion shaft. Other companies used tapered roller bearings that can handle a tremendous amount of this fore-and-aft thrust while spinning with ease but the Ferrari style comes apart and destroys the gears.

My solution is to replace the sliding inner race roller bearing and the deep groove ball bearing with a pair of tapered roller bearings. This photo is a 250 GT Lusso center section with the “chicklet” style limited slip differential. On some axles I’ve install tapered roller bearings to support the differential but on the later axles there isn’t much room to install this type of bearing and I have found the original ball bearing set up to be adequate. I have done this conversion to many cars that have gone many thousands of miles with no issues.

Final drive Ferrari

GT Ferrari 250 Axle Center section

After overhauling dozens and dozens of Ferrari transmissions I have a good idea on what to expect when the case is opened up and shafts are broken down. Whether it’s a 250 GTE 4 speed, a 246 GT Dino trans-axle or a 330 GTC/Daytona style 5 speed trans-axle,  synchronisers on Ferrari’s do not last many miles however, the rest of the components are over built and hold up well.. The bearings and gears are over built and the machined parts like flanges and shafts are impeccably machined using incredibly hard steel. The transmissions have oil pumps that pressurize the main and lay shafts to keep everything thoroughly lubricated so the bearings that the gears turn on are flooded in a pillow of oil.

This transmission out of this 250 shifted well but had the typical severely worn synchronisers so I was prepared to perform the “normal” repair of cleaning, inspecting and replacing the end bearings and synchros. This trans had been run without oil for a long time and the bearings in the photo were so wiped out that there was about .020″ clearance between the gear and bearing where there should only be about .005″. How did this thing work at all?

250 GT transmission overhaul

Transmission overhaul bearings

Bearings Ferrari transmission

Here are some more photos of the GTE transmission that I am overhauling. Everything else looks fine inside, we are replacing all of the bearings and synchroinzer bands. The main shaft and lay shaft gears are all in excellent condition.

Transmission

Gears for mainshaft and layshaft

but the gears and spacers are all good.

Last month we removed the transmission on a 250 GTE to have the overdrive that was inoperative inspected and rebuilt. When our friend John returned it to us, he mentioned that the filter on the overdrive was packed with metallic fragments that must have come from the transmission since nothing metallic matching this debris came from the overdrive. He told me that without removing, inspecting and super cleaning the transmission, there is no way the overdrive would last more than a few thousand miles.

I could not imagine what could have been a problem since it shifted well and was quiet when I drove the car prior to the tear down.

Yesterday I began to take the transmission apart and found that the Boccola ingranaggio, or 1st, 2nd and

250 Transmission gear

Bushing for 2nd gear

3rd, gear bushing style bearings are all torn up and the lead/tin coating has been wiped off the surface, probably from a low oil condition. I bet there was a pound of metallic sludge in that overdrive brass screen filter.

Here is what thousands of hours of detailing a Ferrari Lusso engine looks like. It is dusty and not totally finished but getting close. If I had a driveshaft I would take her for a spin! Really looking forward to driving the car because we did some enhancements to the engine and installed a overdrive transmission to make the car that much better and faster.

Engine to the Lusso

Here is what amounts to about $5000 in labor, the front suspension on a Ferrari 250 completely overhauled and detailed.

New pins and bushings, proper finishes and hopefully it will look this good for more than a few years!

90,000 miles on a Ferrari

Cleaned up, overhauled and detailed

The Oliver 2050 with the forklift makes getting cars off jack stands or a rotisserie quite easy. Now this Ferrari 250 GT Lusso is outside and positioned high in the air for sand blasting and painting the engine bay.

The Lusso is being restored in a way that many would think is backward, but it is actually quite prudent. Most people would chose to restore a car from the outside-in making it look the part and then worrying about mechanicals later – but risking a basket case under thousands of dollars in paint.

Our client has chosen restoration from the inside-out, focusing on meticulous restoration of the running gear of the car. The engine was rebuilt with period performance modifications, cams, and porting. The suspension was nickel plated and all fasteners were black oxide treated. This is a very detail oriented work, but the car completed in the condition it was in when leaving the factory – save for the paint. Read about the suspension here and here.  And the drivetrain here. Watch the engine run here. To see all related Lusso posts click the “Lusso” link under the categories heading on the right.

The exterior of the car should have paint, but it’s an option left to the current owner, or an option for a future owner down the road.

After sending off all the various parts for re-finishing, the front suspension to the Lusso is finished. Karl replaced the bushings and pins and the pivots operate smoothly without a hint of play. The black parts are powder-coated and the arms are nickel plated. I located enough of the button style grease fittings to complete the job once it is on the car.

Even thought the pins and bushings were tight, it is amazing how worn down they were. The outer links had the original phenolic bushings which disintegrated upon removal and the pins were rusted and pitted beyond re-use. The big inner pins were excellent but the bushings were worn severely so now, everything is as new and ready for assembly to the car.

Rebuilt front suspension for Ferrari 250

Here are the before and after photos that show how nice things can look when they are detailed properly

Original and cruddy front suspension

After detailing all of the hardware and countless hours adjusting the pinion depth, pre-load, back lash and differential pre-load, the Lusso axle is finished. I really wish Ferrari took notes from GM when building these axles, the amount of shims and in and out of the parts practically destroys the housings before evertyhting is adjusted.

The axle tubes are powder coated and all hardware is black oxide finished. The pinion is converted to tapered roller bearings. The brakes are all new and once I get the tube nuts back from the plating shop, I can finish up the plumbing for the brake fluid.

Rear axle assembly for a Ferrari 250