Trek Shock Guide

This is for guidance only. You are responsible for verifying clearance on your frame. Mount kit measurements should be checked (especially for older frames.)

You can find Trek bolts here.

Shock mount hardware is available here.

FUEL EX

HARDWARE

MY Start	MY End	Travel	Eye-to-eye	Stroke	Mount-kit U/F	Mount-kit L/R	Notes
2005	2006	100	165	38	6x40	6x21.8
2007	2007	100	165	38	6x40	6x22.2	Models: 5/ 6
2007	2007	120	190	50	8x40	8x22.2	Models: 7/ 8/ 9/ & Carbon
2008	2008	120	190	50	8x40	8x22.2	Models: 5.5/ 6.5
2008	2008	120	190	50	8x40	8x34	Models: 7/ 8/ 9/ & Carbon
2009	2009	120	190	50	8x40	8x22.2	Models: 5.5/ 6.5
2009	2009	120	190	50	8x40	8x40	Models: 7/ 8/ 9/ & Carbon
2010	2011	120	190	50	8x40	8x40	Models: 5/ 6/ 7
2010	2011	120	184	50	10x40	8x40	Models: 8/ 9/ & Carbon
2012	2012	120	190	50	8x40	8x40	Models: 5/ 6
2012	2012	120	184	50	10x40	8x40	Models: 7/ 8/ 9/ & Carbon
2013	2013	130	190	50	8x22.2	8x40	Models: 4
2013	2014	130	184	50	10x40	8x40	Models: 5 & higher
2014	2015	120	184	48	10x40	8x40
2015	2016	120	184	48	10x40	8x40
2016	2016	120	184	48	10x40	8x40	Models: 5/ 7
2016	2016	120	184	48	10x40	8x50 Offset	Models: 8/ 9/ 9.8/ 9.9
2017	2019	130	210	52.5	10x54/60	8/10x50 Offset
2020	2022	130	210	52.5	10x54	10x50 Offset	27.5 Wheel
2020	2022	130	210	55	10x54	10x50 Offset	29 Wheel

BOLTS

Lower Shock Axle – 599899 Upper Shock Axle – 599898

Additional bolts are only required for Thru-Shaft to standard shock conversion. For DRCV conversion you will need a “DRCV retrofit kit”

SHOCK COMPATIBILITY (GEN 6)

Brand	Coil	Air
Fox	DHX	Float X
RockShox	Yes, all Shocks	Yes, all Shocks
DVO	Yes	Yes
Push	*	N/A
Ohlins	Yes	Yes
Intend	N/A	Yes
CaneCreek	Yes	Yes
Marzocchi	Yes	Yes
Fast	Yes*	N/A

Push* - Push do not offer ElevenSix for this frame

Fast* - We are yet to confirm clearance of the Evo variant

FUEL EX E

HARDWARE

MY

Start

MY

End

Travel

Eye-to-eye

Stroke

Mount-kit U/F

Mount-kit

L/R

Notes

2023

-

140

205

60

Trunnion

M8x40

SHOCK COMPATIBILITY

Brand	Coil	Air
Fox	DHX	Float X
RockShox	Yes, all Shocks	Yes, all Shocks
DVO	Yes	Yes
Push	Not offered	N/A
Ohlins	Yes	Yes
Intend	N/A	Yes
CaneCreek	Yes	Yes
Marzocchi	Yes	Yes
Fast	Yes*	N/A

Fast* - We are yet to confirm clearance of the Evo variant

RAIL

HARDWARE

MY

Start

MY

End

Travel

Eye-to-eye

Stroke

Mount-kit U/F

Mount-kit

L/R

Notes

2020

2022

150

230

57.5

M10x54

M10x40

2023+

-

160

230

65

M10x54

M8x20

Gen 6

BOLTS

Trek Rail - Gen 3:

Lower Shock Axle – 5258210 Upper Shock Axle – 5258209

Trek Rail - Gen 2:

Lower Shock Axle – 599900 Upper Shock Axle – 599898

Trek Rail - Gen 1:

Lower Shock Axle – 599900 Upper Shock Axle – 599898

Additional bolts are only required for Thru-Shaft to standard shock conversion.

SHOCK COMPATIBILITY

Brand	Coil	Air
Fox	DHX2	DPX2, X2*
RockShox	No	Deluxe (in-line shock)
RockShox Flight Attendant	No	No
DVO		No
Push	No* (SS Casting)	N/A
Ohlins	Yes	Yes
Intend	N/A	Yes
CaneCreek	No	No
Marzocchi	No	No*
Fast	Fenix Enduro*	N/A

Fox X2* - In theory this shock fits, however, it is “too close for comfort” and any flex in the frame may cause the shock to collide with the frame. We would recommend against fitting X2.

Push* - Once upon a time Push made an ElevenSix SS (side stack) with offset adjusters and a perpendicular reservoir which allowed the shock to clear the frame. Any other generation of the ElevenSix will not fit.

Marzocchi* - We are yet to confirm whether the Marzocchi Bomber Air is compatible.

Fast* - Only the standard Fenix Enduro (not Evo) shock with a perpendicular reservoir will fit.

REMEDY

HARDWARE

MY Start	MY End	Travel	Eye-to-eye	Stroke	Mount-kit U/F	Mount-kit L/R	Notes
2014	2016	140	197	57	10x40	8x40	27.5
2014	2016	140	197	55	10x40	8x40	29
2017	2017	150	230	57.5	10x60	8/10x50 Offset	Lower bolt size depends on the model
2018	2018	150	230	57.5	10x54/60	8/10x50 Offset	Lower bolt size depends on the model
2019	2022	150	230	57.5	10x54/60	10x50 Offset

BOLTS

Lower Shock Axle – 540755 Upper Shock Axle – 540755

Additional bolts are only required for Thru-Shaft to standard shock conversion.

SHOCK COMPATIBILITY

Brand	Coil	Air
Fox	Yes, all shocks	Yes, all shocks
RockShox	Yes, all shocks	Deluxe (in-line)*
RockShox Flight Attendant	N/A	Yes
DVO	Yes	Yes
Push	*	N/A
Ohlins	Yes	Yes
Intend	N/A	Probs
CaneCreek	Kitsuma Coil	Kitsuma Air
Marzocchi	Yes	Yes
Fast	Yes	N/A

RockShox Deluxe* - might not perform very well/ consistently on a long travel ebike due to lower overall oil volume

Push* - Push do not offer ElevenSix for this frame

SLASH

HARDWARE

MY Start	MY End	Travel	Eye-to-eye	Stroke	Mount-kit U/F	Mount-kit L/R	Notes
2012	2013	160	210	60	10x40	8x40
2014	2016	160	210	60	10x40	8x40
2017	2020	150	230	57.5	10x54/60	10x50 Offset
2021	2022	160	230	62.5	10x54	10x40

BOLTS

Trek Slash (2021+):

Lower Shock Axle – 5258210 Upper Shock Axle – 5258209

Trek Slash (pre-2021):

Lower Shock Axle – 540755 Upper Shock Axle – 540755

Additional bolts are only required for Thru-Shaft to standard shock conversion.

SHOCK COMPATIBILITY (2021 & NEWER)

Brand	Coil	Air
Fox	Yes, all shocks	Yes, all shocks
RockShox	Yes, all shocks	Deluxe (in-line)*
RockShox Flight Attendant	N/A	Yes
DVO	Yes	Yes
Push	*	N/A
Ohlins	Yes	Yes
Intend	N/A	Probs
CaneCreek	Kitsuma Coil	Kitsuma Air
Marzocchi	Yes	Yes
Fast	Yes	N/A

RockShox* - Standard Super Deluxe Air does not fit due to lock-out lever interference in the last 1/3 of the travel

Push* - Push do not offer ElevenSix for this frame

TOP FUEL

HARDWARE

MY Start	MY End	Travel	Eye-to-eye	Stroke	Mount-kit U/F	Mount-kit L/R	Notes
2008	2008	100	165	38	8x40	8x22.2
2009	2012	100	165	38	8x21.8	8x35.6
2016	2016	100	165	38	8x25.4	8x50 Offset
2017	2018	100	165	38	10x54	8x50 Offset
2020	2021	115	190	45	8x40	8x26
2022	-	120	185	50	Trunnion	8x30

SHOCK COMPATIBILITY (2022 & NEWER)

Brand	Coil**	Air
Fox	DHX, DHX2	DPS, DPX2, Float X
RockShox	Deluxe, Super Deluxe	Yes, all shocks
RockShox Flight Attendant	N/A	No
DVO	Jade	Topaz
Push	*	N/A
Ohlins	*	*
Intend	N/A	*
CaneCreek	*	*
Marzocchi	*	*
Fast	*	N/A

Coil Shocks** - this frame is not very progressive and it is much better suited for air shocks

Push* - Push do not offer ElevenSix for this frame

Ohlins Coil* - Only with transverse casting

Ohlins Air* - This shock will likely fit, however, we are yet to confirm this

Intend* - This shock will likely fit, however, we are yet to confirm this

CaneCreek* - We are not sure due to end eye design

Marzocchi Coil* - IFP reservoir will need checking for clearance!

Marzocchi Air* - Similar in design to Float X, however, it still needs checking for clearance

Fast* - Needs checking for clearance at full travel, the Evo version of the shock might not fit

Super Deluxe Thru-Shaft (C1 2021+)

The RockShox Super Deluxe Thru-Shaft shock is a proprietary shock designed explicitly for Trek Bikes and not available on any other frame manufacturer’s bikes. The Thru-Shaft is fitted on a range of Trek frames including the Slash and the Rail.

Most mountain bike shocks use an internal floating piston (IFP) design. The IFP sits between the oil and gas [typically nitrogen] inside the shock. When you hit a bump, the shock damper shaft displaces the oil as it moves through the shock, pushing against the IFP and compressing the gas below. The IFP returns to its position when you are over the bump and the oil pressure is reduced.

The idea behind the Thru-Shaft design is to remove the perceived lag created by using an IFP. Instead, the design introduces a secondary damper rod to account for the change in oil volume, and the damper shaft ‘exits’ the bottom of the shock.

On paper, it may seem like a great idea, but the Thru-shaft design has suffered reliability issues. A rod protruding from the shock requires an additional seal to retain the oil in the damping circuit - and in practice, another seal means another point of possible failure.

As production of these shocks is limited to Trek Frames this product is less well supported in terms of spares and parts than another more widely available/ equivalent suspension. This means that these shocks are generally more challenging, or sometimes even impossible to service or repair.

On balance and in our experience, the performance and maintenance issues of the Thru-Shaft outweigh the stated benefits of this suspension design.

CAN I REPLACE MY ROCKSHOX THRU-SHAFT SHOCK WITH A STANDARD EYELET SUPER DELUXE AIR/ COIL SHOCK?

The frame/ shock clearance varies between frames and frame model years - please refer to the compatibility tables on top of the page for per-frame & model year compatibility. The reservoir on the Thru-Shaft shock is placed much higher, towards the upper eyelet (trunnion), and offset to one side in relation to the IFP reservoir on a standard Super Deluxe to improve the frame clearance. See the image below for a comparison.

CAN I REPLACE MY ROCKSHOX THRU-SHAFT SHOCK WITH A DIFFERENT TRUNNION?

No, not without drastically affecting the bike’s geometry. Despite the Thru-Shaft shock using trunnion mounts, it is a 230mm eye-to-eye shock. See the image below for a comparison.