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This is a summary of a thread that many MTF members contributed to last summer. The purpose of the thread was to figure out exactly what modifications/components must be added to a standard JD X700 series GT, in order to operate a Front End Loader like the JD 45 FEL.

This information should be applicable to the JD X700, X720, X724, X728, X729, X740, X744, X748, and X749, as well as any of the predecessor models in the earlier X4x5 and X5x5 series. With the caveat that JD does not market their FEL for the All-Wheel-Steer versions.

The original thread where this information was discussed can be found here. If anyone would like to continue discussing the information, please post to that thread. If we find that corrections need to be made here, we can ask the mods to unlock this thread.

Necessary and Optional Hydraulic Components for Operating an FEL on the JD X700 Series GTs:

- Hydraulic Coupler Kit (Part No. BM20761):

AKA "SCV", standard equipment on X700-series except the base X700 model

- Transaxle Hydrostatic Relief Valve (Part No. 15043 or 15044):

Some argue that the THRV is not necessary because the TT K92 tranny already has an internal pressure relief valve. However, the existing valve is an implement relief valve, not a hydrostatic transmission relief valve.

Like all of Tuff Torq's HSTs, the TT K92 hydrostat normally gets "relief" when necessary by spinning the tractor wheels. But when the weight of a loader and ballast are added, under certain conditions it could be difficult for those wheels to spin and "relieve" the transmsission when overloaded. So that is where the THRV [Transaxle Hydrostatic Relief Valve] comes in.

The THRV is installed on the top of the transmission (under the seat and gas tank), in the location where the existing Forward Free Wheeling Valve is installed (there is also a Reverse Free Wheeling Valve, which remains intact). The FFWV is removed, and the THRV is installed in its place. The THRV then also doubles as the FFWV.

[Note: The TTK92 "shimming" described here occurs in the already existing Implement Relief Valve. That is the valve under the hex head, just to the left of the THRV seen here in Wooly's photo, post #11.]

- Free-Wheeling Valve Control Lever (Part No. M146148):

A FWVC Lever is standard equipment on X700-series tractors. It allows the tractor to be pushed/rolled when the engine is not on, by relieving the hydraulic pressure lock in the transmission.

Because the replacement THRV is taller than the standard FFWV, the existing Free Wheeling Valve Control Lever (which actuates the Forward and Reverse FWVs) must be swapped for one that will fit the taller THRV. Again, see Wooly's photo.

- Hydraulic Cylinder Lock-Out Valve (Formerly Part No. AM131526 - now replaced by Part No. AM134625):

AKA "Diverter Valve". This part gets installed on the SCV, to lock-out other implements from the hydraulic loop (such as the mower deck or 3 Pt. Hitch). Some have reported that JD may not be including/recommending this part any longer. Others have said it is still included with the Quick Hitch package. Check with your JD dealer.

- Regenerative Bucket Kit (Part No. BM22220 $63.00, formerly Part No. BM20911)

The regenerative bucket kit is available to improve bucket cycle times. It adds a fourth position on the hydraulic control lever, which allows the bucket to dump very quickly (as long as there is weight in the bucket).

The "kit" amounts to a replacement valve for the SCV. According to MTF member EngineTech, "You remove one of the linkages [from the SCV], take off the cap, slide out the old spool, and slide in the new. There are some springs involved too I think."
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