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Old 12-14-2018, 05:54 PM
DBailey's Avatar
DBailey DBailey is offline
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Join Date: Dec 2009
Location: Northern California
Posts: 134
Default It's your gearbox

Hi--It is for sure your gearbox having issues. If it pops out of 3rd, won't go in, grinds, it is related to the 3-4 synchronizer unit (not the synchro ring) and the way it engages with the teeth on the gear. This can be caused by worn teeth on the gear, excessive end play of the gears on the mainshaft(thrust washers),worn synchro unit, bent shift forks, worn shift forks, worn shift assembly (at shifter) Sounds like if the box has been worked on it wasn't done properly. The gearbox is strong and tough--this is maybe a $1000 repair, no need to spend 5k to 6k.

Also make sure you are using the correct fluid in the trans. The worst thing you can do to a Box with composite synchro's is to use other that the manufacturer's recommended fluid. (on WC T5, 3550's, T56, etc only Dextron ATF)

What can also cause shifting issues is the clutch disc weight and size.

Unless you have spent a lot of time shifting dog boxes you will be slower with one until you get proficient with it.
Most dog boxes are used with small 5"-7" clutches and this has a huge effect on the way they shift.

Hope this helps, Dean
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Old 12-19-2018, 08:06 PM
MattChoj MattChoj is offline
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Join Date: Apr 2014
Posts: 25

Kyle -- for what its worth...in the video you attached, I'm starting in third as well.. I realize we have very different cars, but I would look at changing your rear gear before spending the $$$ on the dox box... just my opinion.

PS - thanks for posting that video.... it was a interesting perspective.
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Old 01-04-2019, 03:00 PM
KyleJones KyleJones is offline
Join Date: Dec 2018
Posts: 6

Well I already have a 4.10 so I guess that caddy engine makes a lot more torque than my iron head 305 that hasn't been refreshed since... I've owned it

FWIW I've taken 130 lbs off mostly the front end with more savings to come. I was running last season 200 lbs over my minimum weight ...I know I'm embarrassed for myself Still won't be setting the Waterford track record like you but it's directionally correct

I decided to go ahead with faceplating. Liberty's package for the TKO is about $600 plus any parts that need to be replaced in the rebuild. I figure for that price it's worth it to try it and see.
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