Traxxas Summit suspension bind fix

The Traxxas Summit is an amazing RC beast, and like any machine, it needs maintenance. With my inkling to make my Summit perfect, I did multiple things like servicing the shocks, upgrading the transmitter and receiver etc. All was going well until I started noticing something. 

I had to increase the pre-load on the shocks a lot to get the suspension responsive. When I compared mine to a new Summit which had quite plush suspension, mine was performing really bad, and felt like it was binding really bad.

This write-up will walk you through my troubleshooting process and what fixes were done.

Observations:

• Non-retractable sag on the rear end – With this, once you press the rear of the Summit down, it does not come almost all the way up on its own. You have to pull it back up to reach the fully upright position.
• Rough suspension travel – There was very little spring action in the suspension. Even when you press it, it felt as if something was gripping the suspension without letting it spring back with the coil spring action and get dampened by the shocks.
• Sub-par cornering ability – With the suspension not taking care of the rolling of the body in tight turns, the Summit easily rolled over despite the harder and wider Big Joe racing tires I run.

I reached out to the ever so active and helpful Traxxas forum for the Summit, and got a suggestions for a bunch of things to try out. Below I am summarizing what I did to to remedy my situation while including what else it could have been too (images added way below). 

The forum thread I opened can be found here.

Troubleshooting:

• Kept the Summit on a smooth surface like a counter-top and try pressing the chassis down and observe the way it comes back up. With no significant resistance for the wheels to hold back the retraction, the suspension was still rough and wasn’t getting up on its own.
• Disconnected the shocks and springs. I did not check the shock oil levels or if the shocks were stuck coz I had already serviced them.
• After the shocks were disengaged I tried moving the suspension link up and down while the vehicle was elevated. It should ideally be quite loose coz there should be very less resistance from the rest of the components. Even with the shocks and spring disengaged it was feeling very rough. Even the wheel's weight was not sufficient to bring it back down again.
• If the suspension was moving up and down freely, this would be a good time to check the shocks coz it is likely to have the issue. (But this wasn't the case for me – so moving on).
• Next easiest thing to check and prone to damage are the rocker bearings. Disconnected the push rods from the rockers, and checked if the rocker 'rocked' freely. In my case, it was perfect and smooth, just like how it should be. If you notice it to be rather tight, replace the bearings.
• At this point it looked like it could be either the A-Arm pins or the rod ends or the axle carriers.
• I disconnected all push rods and toe links and checked if there was any roughness between the rod ends and pivot balls. There was a little bit of roughness, but that was not big enough to create what I was experiencing. However, I made it a point to pop out all pivot balls and clean them up as well as the insides of the rod end holes.
• With only the A-Arms and axle carriers connected, the suspension was still rough.
• Next thing to check was the pivot balls on the axle carriers. I took the wheels off at this point.
• One thing I recommend you doing at this point is to use the suspension multi-tool and loosen both the pivot balls a bit and see if the linkage starts moving freely. This is a step I should have done before taking the axle carrier off (Or even at the very beginning just after disconnecting the shocks. That would save you from removing too many parts). If the suspension starts moving freely at this point, the reason is the pivot balls are stuck due to dirt getting in through damaged rubber boots. This was my situation.
• I took the axle carriers off, removed the pivot balls and cleaned them up well, and put in new rubber boots replacing the broken ones.
• After that I attached the axle carriers back to the A-Arms and then adjusted the pivot ball caps just snug enough to hold it steadily but does not grip the pivot ball tightly. At this point the suspension link traveled with very little resistance.
• One point to note about the dust boots is that, you should not attach the ring retainers for the dust boots before tightening the pivot ball to the A-Arm. Keep it unattached and put it on once the pivot ball screw is well in to the A-Arm. Else you will be unnecessarily twisting the dust boot, and it will damage it.
• So, after I put all cleaned up components back together the suspension travel was very smooth and solid!

If the above was not the cause for the issue, there was a couple of other things it would have been - which I would have found if I went further.

1. A stuck A-Arm pin due to dirt.
2. A bent A-Arm pin.

Hope this helps troubleshoot stuck suspension of your Traxxas Summit (or even the E-Revo)

The suspension link does not drop even under its own weight!

The culprit! The damaged boots have made the pivot balls go rough with dirt.

Dust boots taken out. At this point the pivot balls were really tight!

All pieces cleaned up and drying out in the air!

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New dust boots installed on clean axle carriers