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This ribcase transmission comes with a modified front cover and an upgraded seal.

NOTE: If exchanging smoothcase to a ribcase, the shift lever is different.  You will need a ribcase shift lever part number: U-22G1397.
(Remember: it runs straight SAE 30 weight motor oil for lubrication- not gear oil)


The ribcase gearbox is the strongest of boxes for the Sprite, Midget and Morris Minors application and can be one of the most dependable parts of your car. These boxes use real bearings in all the critical places (in contrast to the 'smooth case' box that uses simply bushes).

The ribcase is a direct replacement for the smooth case of old and will provide a much improved gear ratio set. The first gear is taller and thus much more comfortable and usable to drive.

And stop believing that every ribcase will pop out of second gear! We believe the reputation of the Spridget gearbox has been severely hurt by rebuilders that don't know how to do it right!

All of our gearboxes are built in house! We even disassemble those we might buy as rebuilt from the UK and FIX them right! They are Guaranteed to be good and we promise, THEY WILL NOT POP OUT OF SECOND GEAR!

These are sold with a core charge to ensure our supply of ribcases to rebuild. You might also consider our rebuilding service if you have the time. The standard service requires that you send us your gearbox (easily shipped by UPS), we do a complete inspection and provide a quote for rebuilding it.

 Returned Core must be Ribcase to qualify.

Need Your Spridget Ribcase Transmission Rebuilt?

Transmission Rebuilt 1275 Ribcase , Sprite & Midget

Transmission Rebuilt 1275 Ribcase , Sprite & Midget

Transmission Rebuilt 1275 Ribcase , Sprite & Midget

Transmission Rebuilt 1275 Ribcase , Sprite & Midget

Transmission Rebuilt 1275 Ribcase , Sprite & Midget
Part No: RJM1109E
$1999.95
Qty:
Specially Priced. Discounts Do Not Apply.
This Item has a $350.00 core charge.
Fits the following:
Sprite & MG Midget

This ribcase transmission comes with a modified front cover and an upgraded seal.

NOTE: If exchanging smoothcase to a ribcase, the shift lever is different.  You will need a ribcase shift lever part number: U-22G1397.
(Remember: it runs straight SAE 30 weight motor oil for lubrication- not gear oil)


The ribcase gearbox is the strongest of boxes for the Sprite, Midget and Morris Minors application and can be one of the most dependable parts of your car. These boxes use real bearings in all the critical places (in contrast to the 'smooth case' box that uses simply bushes).

The ribcase is a direct replacement for the smooth case of old and will provide a much improved gear ratio set. The first gear is taller and thus much more comfortable and usable to drive.

And stop believing that every ribcase will pop out of second gear! We believe the reputation of the Spridget gearbox has been severely hurt by rebuilders that don't know how to do it right!

All of our gearboxes are built in house! We even disassemble those we might buy as rebuilt from the UK and FIX them right! They are Guaranteed to be good and we promise, THEY WILL NOT POP OUT OF SECOND GEAR!

These are sold with a core charge to ensure our supply of ribcases to rebuild. You might also consider our rebuilding service if you have the time. The standard service requires that you send us your gearbox (easily shipped by UPS), we do a complete inspection and provide a quote for rebuilding it.

 Returned Core must be Ribcase to qualify.

Need Your Spridget Ribcase Transmission Rebuilt?

 
 
Question:
I have a MG Midget 1973 with 4 speed gear box. My question is. Do you have the conversion KIT FOR 5 Speed Gear Box?
Answer:
Yes we do. It's not normally stocked but we offer the conversion kit here: https://www.minimania.com/part/C-12345R/5-Speed-Conversion-Kit-With-Crank-Seal-On-Backplate--Sprite--Midget

Spridget Mania Tech Team

The Spridget Parts and Accessories Experts

 
 
 
 
Question:
Replacing a 1098 sprite engine with a 1275. A previously rebuilt ribcage trans has not been used will bell housing and clutch lever from 1098 transfer to 1275. Which clutch and flywheel should be used with 1275?
Answer:

The 1098 engines on the Sprites always had a ribcase from the factory - only the 948cc engines used the earlier smoothcase. So, the ribcase will mount to the 1275 with no issues since it didn't change when the 1275 came along. The only exception to this is that the release fork and release bearing do need to be the 1275cc type as the 1098 type was different. The flywheel for the 1098 and the 1275 are not interchangeable since the 1098 had a 4-bolt flywheel and the 1275's are a 6-bolt flywheel. The 1275's use the 1275 type clutches.

If you get a full 1275 clutch kit, it will come with the appropriate release bearing.

Spridget Mania Tech Team

The Spridget Parts and Accessories Experts

 
 
 
 
Question:
Hi what is the warranty on this transmission?
Answer:
Our transmissions are backed by a 12 Month / 12,000 mile warranty against defects. Depending on how it's used. As these are sometimes added to modified cars, non-standard applications or race use, we want to make sure we know you'll be happy with them, and will take care of any initial issues if any. Give us a call if you have any more questions 1-800-946-2642

Spridget Mania Tech Team

The Spridget Parts and Accessories Experts

 
 
 
 
Question:
I have a 1275 rib cage in a 1973 midget I’m wondering how the average price to have one rebuilt compares to turning one in as a core and purchasing a rebuild I have plenty of time.
Answer:
For shop work, the price is just parts + labor required. Depending on any issues with the unit, it can be anywhere from 1100+ And yes, it can be over the price of the exchange if there are problems that require significant time. No way to know without having it here to inspect and quote. Give us a call and we can arrange it.

Spridget Mania Tech Team

The Spridget Mania Parts and Accessories Experts

 
 
 
 
Question:
I need to know the availability and cost for a complete refurbished gearbox for Morris Minor Traveller LHD, engine 948 cc, year 1976, Chassis MAW 3748105. The gearbox must be shipped to Italy. Do you need my gearbox in return? Matteo
Answer:
We do offer the upgraded ribcase transmission  https://www.morrismania.com/part/RJM1109E/Transmission-Rebuilt-1275-Ribcase--Sprite--Midget
This will have a core charge with it so returning yours would not be practical.
ETA currently is apx. 6-10 weeks out, and could be longer.
You can place an order on the website if you like and we will get a shipping quote for you before we process the order.

Spridget Mania Tech Team

The Spridget Parts and Accessories Experts

 
 
 
 
Question:
Do you recommend 30wt oil in the rib case over 20-50?
Answer:
Yes for a Ribcase trans the best choice is a straight 30wt engine oil.

Spridget Mania Tech Team

The Spridget Parts and Accessories Experts

 
 
 
 
Question:
Hi , I am just enquiring about a RibCase Gearbox to fit to my Morris 1000 A Series Van. I see you sell these as an exchange ? Am i able to purchase a gearbox outright ? I have filled out the shipping quote section , but it wont give me a shipping quote to Australia ? My address in Walya Place Mandurah Western Australia post code 6210 Thanks in advance
Answer:
Hi,
We can sell you a transmission outright, but you would have to pay for the core charge as well. Returning yours would cost more than it is worth most likely. Let me work up a shipping quote and I will get b ack to you in a few days. We will also need to know if it is a LHD or RHD. if you do decide to purchase one.
thanks,
 
 
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