Gen 2 SuperMaxx UltraLite 7.5 Differential Kit/ 8 Spyder

Original price was: $375.00.Current price is: $249.95.

Only 2 left in stock

SKU: 13540B Category:


7.5 Differential Gear set for the Maxx (1/8th scale gears) 8 gear spyder setup

As some of you know I’ve been developing a much stronger differential for the Maxxs for some time now. Tremendous research and development went into the selection of the gears and the design of the differential. Countless hours of testing have revealed that this is a bombproof solution the High Powered Maxx’s differential needs.
We’ve selected the 7.5 gears as the standard. There is a wide variety of differential styles available from open 6 spyder design to torque sensing differentials.

The first offering I’ll be making to the Maxx community will be a differential that fits inside the standard Maxx bulkhead.

7.5 Differential Kit includes:
● SuperMaxx UltraLite 7.5 Gear Case (~35 grams)
● Differential Gear Set, 7.5, 8 Spyder 13543
● Helical cut Ring and Pinion Gears
● Diff Cup and pins.
● Huge 8mm x 16mm Rubber Shield Bearings
(these are the really good ones)
● SM hardened pinion drive cup
● SM hardened Output Drive Cups & Shafts
● Shim kit
● Detailed set-up instructions
and everything else you need to set up a complete truck

● Kit is made from top quality 7075-T6 billet aircraft aluminum.
● Finish is natural and Polished to a high luster
● Installation requires grease
(diff loc lube if desired) and blue loctite
● Allows proper Ring gear orientation for
both T & E Maxx
These can be used in the T or E Maxx.
E-Maxx has the ring gear installed on the opposite side as the T does. You must either put the ring gear on the correct side or run your motors/transmission backwards (which is a major No-No.)
We’ve even gone so far as to mark the inside of the case so you know which side to put the ring gear on.

The outputs are compatible with UE and MIP CVs. The Dynamite & XTM CVs drive cup is 3.5mm longer – which probably means that the shafts are 3.5mm shorter and will be too short. Stock Plastic sliders will not work. XTM center shafts will not fit the pinion. A Center Shaft kit for the XTM chassis is now available.

Lubricants are not included. Due to so many different selections and options (for traction control) on silicone oil for inside the carrier (where the spyders are) we’ve elected not to include them. At $10 a bottle it would drive the price up pretty quickly. For the Ring and Pinion use a premium quality grease (I get mine from the local auto parts store.)

These do lower your overall gear ratio, you will need to gear your truck up.
Maxx R&P ratio is 2.85:1
7.5 R&P ratio is 3.31:1
For this reason you must upgrade both ends of the truck at the same time. Do not try to mix ratios.

If running 22/72 with the Maxx ring and pinion, 23/65 would be the identical ratio with the 7.5s
I’m running 22/66 at the moment. It has tons of bottom end, but feels like it could use some more top. Though there is no question the truck is fast even on a large track. (I had a 23 but it had a problem and I’ve not gotten it replaced yet.)

We will also offer an adapter kit which will allow those of you with stock gears to run them in the UltraLite case. This for those of you who want a stronger housing, but are not ready to take the plunge all the way into new gear sets.

Hope you all like these.
These are high precision gears, setup is critical for long life and smooth operation (same as in full sized cars and trucks.) While the instructions are very detailed on how to do this, it’s not quite as easy as put screw A in hole B. Patience and following the instructions will ensure success.

Additional information

Weight 1 oz
Dimensions 1 × 1 × 1 in

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