R8 353 Gearbox

[cbx6_79]

Hello!
I see there is a lot of old Renault knowledge on this forum, so I thought I could send out a question
I have a R8 1135 with a 353 gearbox (5 speed). I have had some of theese cars at the late 70's, and as I remember the gearbox was always tagged 353-03.
The one I still have, the gearbox is tagged 353-13. Have checked with the parts catalogue, and see that even 353-33 exist. Is anyone here familiar with the differences bbetween these dashnumbers -03, -13 and -33?
The 353-13 gearbox I have, I got NOS as a spare at the end of the 70's, and it had the later type bellhousing, with the support tube for the thrust bearing.
It also was delivered with the brackets to bolt up the LH and RH side rubber mounts, and make them solid.
Brg Jan from Norway

 

[Wheelers Workshop]

Hi Guys,
Seems like my suspicions were correct, so looking at what is salvageable from your "broken 385box" now that all is revealed, the little top shaft needle roller input bearing if its still good can be removed and reused in say a 353 box, I think that Steve has covered the 5th end issues with the later double ball race bearing.

So you have a serviceable 385 Crown wheel and Pinion as a matching pair[ check that the etched numbers match] and as Steve advises, the top shaft and loose gears from another donor box [ 395 or earlier 385?] will give you all the oily bits to fit into a 330/353 box as a Big Box conversion. This gives you a 3.875 final drive and a taller 5th gear [0.86] , great for cruising on motorways. this will require for the 11mm external spacer and shortening of the sun wheel splines and re-splining of the universal joints inner yokes. there is also some light clearance machining around the crownwheel area of the box to do on the early cases.

Alternatively you could reuse all your 353 1st to 4th gears to give a close ratio box with a tall 5th [from your broken donor box] by swapping the 5th synchro inner hubs around unfortunately your lower original 353 5th gear[1.03] has course splines, while the 385 donor pinion has fine splines. I have seen conversions where the fixed 353 5th lower gear on the pinion is machined to fit the fine splines.

In the unlikely event of you finding the Holy Grail 365 box from a early R17 Gordini with Bosch injection that has a 0.93 5th gear which I use in my 8 Gordini. This gear train is the best Factory set available with close ratios close to 353 and bigger improved synchros.
Hope this helps,
Cheers
Dave

 

[cbx6_79]

Thanks Dave @Wheelers Workshop for all the information. I am impressed with all the knowhow that comes from you and Steve. It has been a great help. As you suggest, I will take the small bearing from the input shaft from the 385, and replace the damaged one on my 353-13 box. The rest of that 353-13 box is in good shape, and I can assemble that one again. Will then see what to do with the rest of the 385 parts. Crown wheel and pinion seems to be a match, ref photos. Even if I take all the mods needed to get it into a 330 housing, I will still be missing the modified universal joints, and they are also hard to get? A R17 Gordini 365 gearbox I will probably never get sight of here in Norway, believe none ever imported.
Thanks again!