Lola Transverse Indy/ChampCar Gear Change

Lola began using a transverse gearbox in 1994.  They followed the same basic format from 1994 through 1999.  The following is a step by step pictorial depiction showing the removal of all six forward speeds and reverse in a 1999 Lola ChampCar.

Keep in mind while viewing the pictures that power comes in via an input shaft, travels through a set of drop gears which turn a set of bevel gears.  You will see the bevel gears in some of the following pictures.  The output of the drop gear set (not shown) is attached to the "driving" bevel gear shown below.  The "driven" bevel gear then turns the 1st/2nd layshaft which turns the output shaft via whichever gear is selected.  The end of the output shaft has a spur gear which directly drives the ring gear mounted to the differential.

The disassembly process goes in this order-

Drop the underwing and remove the turbo exhaust elbow and exhaust diffuser.  The left rear suspension has been removed in the following pictures to facilitate photography but this is not required nor is it normally done when servicing the gearbox.

Remove the two layshaft access covers and remove both the left hand threaded top layshaft nut and the right hand threaded bottom layshaft nut.  The left hand threaded nut will have a groove cut in the outer portion of the nut to indicate that it is a left hand threaded part.  Note that the 1 7/8 inch socket needed for the top left hand threaded nut will normally need modification to fit between the nut and the gearbox side cover.  The 1 3/4 inch lower right hand threaded socket used on the lower layshaft should work just fine as you buy it.

Use two 1/4-20 screws inserted in the gearbox side cover to carefully pull the side cover off (after removing the side cover securing nuts and the layshaft nuts, of course).  Note that the 1/4-20 holes on the 99 Lola are not through holes as they are on some cars and thus these are NOT JACK SCREWS and should not be used in an attempt to "jack" the side cover away from the main gearbox housing.

Once the side cover is removed you can pull the shift fork pivot rod and remove the reverse, 6th and 5th gears along with their associated shift forks and dog ring.  Removing the shift fork pivot rod will allow you to rotate the shift forks clockwise to disengage the shift fork from the shift barrel so the forks can be removed.  Please note the location and direction of each spacer and bevel washer so they can be put in their proper place upon reassembly.

First through forth gears are separated from fifth/sixth/reverse by an intermediate bearing support plate.  This plate is needed to support the center of the cross or layshafts and counter the spreading force generated by the gears when you start to put torque through the gearbox.  You will need to remove the attachment nuts for this support plate then GENTLY use a small slide hammer with a 10-32 screw to pull the center support plate out.  It is worth noting that I only get into first through forth gears when I am routine service on the gearbox.  On rare occasions I will change fifth and sixth like when going to Road America.

Once the intermediate support plate is removed, you will have access to fist through forth gears.  The driving gears for first and second are built into the first/second layshaft.  Getting the first gear driven gear out of the box will take a bit of patience as the gear is big and there is not much room.  Once all the gears are removed there will be plenty of room to inspect the bevel gear and final drive gear sets.