SD-08 Need Help

[JerryBones]

Hey guys, first time poster long time reader. I’ve searched a ton of threads on here and can’t seem to find a similar issue as mine. Please bear with me As I try to keep it short but o formative!
2018 LTX SE - 3000 miles
Last ride of last season I got the infamous SD-08 code and reverse would not engage. Got home and tore open the chaincase, top gear has some Wear so I swapped it out, checked roller bolts, adjusted chain tension and reassembled, with 16oz of oil. Started sled, engaged reverse 3-4 times moving track each time to confirm it’s going backwards all seems well. I assume I solved the problem. No snow, never drove it.

fast forward to fall I pull the trigger in a 240 hurricane tune, Dalton qay-70 weights, xs825 belt, turbo smart bov etc. Checked clutch offset I was off a bit so my buddy yamamarc walked me through correcting it, removes washer and cut lip behind secondary to get to 58.5mm. Checked driveshaft bearing, hadn’t spun yet, peened it in 4 places and green lock Tight, food to go. Got about 6 inches of snow on Boxing Day so I out about 3 miles on it just to get some breakin on the new belt, nothing high speed everything seemed fine never had a need to use reverse so never tried it. I had to remove the 2 washers on the secondary bolt to get the new belt to come down as it was really high In the secondary. Thought I was good to go
last Night I loaded it on the trailer and went to back up and couldn’t. SD-08 flashes I can hear the actuator moving but it’s not going in gear. Take the actuator off slide my finger in the chaincase and try to manually move over the shift fork and it’s tight it eventually gives way and I can move it freely, reassemble everything and run it , code goes away sled goes in and out of reverse fine, tested 3 times all good, go drive it 30 feet and it won’t go into reverse again SD-08 so I start thinking it’s the actuator maybe just not strong enough, I swap out the one from my dads 2017 tcat, same part number and same result. As soon as I am on the machine and moved 20 feet it won’t go into reverse. Now I’m not sure if I ever fixed the problem from last year or if it’s something to do with the new belt? Also just installed a dalton black orange (updated) in the secondary at 6-2,

sorry for the length of this post I just about tried everything I can think of

 

[JerryBones]

Hey guys, first time poster long time reader. I’ve searched a ton of threads on here and can’t seem to find a similar issue as mine. Please bear with me As I try to keep it short but o formative!
2018 LTX SE - 3000 miles
Last ride of last season I got the infamous SD-08 code and reverse would not engage. Got home and tore open the chaincase, top gear has some Wear so I swapped it out, checked roller bolts, adjusted chain tension and reassembled, with 16oz of oil. Started sled, engaged reverse 3-4 times moving track each time to confirm it’s going backwards all seems well. I assume I solved the problem. No snow, never drove it.

fast forward to fall I pull the trigger in a 240 hurricane tune, Dalton qay-70 weights, xs825 belt, turbo smart bov etc. Checked clutch offset I was off a bit so my buddy yamamarc walked me through correcting it, removes washer and cut lip behind secondary to get to 58.5mm. Checked driveshaft bearing, hadn’t spun yet, peened it in 4 places and green lock Tight, food to go. Got about 6 inches of snow on Boxing Day so I out about 3 miles on it just to get some breakin on the new belt, nothing high speed everything seemed fine never had a need to use reverse so never tried it. I had to remove the 2 washers on the secondary bolt to get the new belt to come down as it was really high In the secondary. Thought I was good to go
last Night I loaded it on the trailer and went to back up and couldn’t. SD-08 flashes I can hear the actuator moving but it’s not going in gear. Take the actuator off slide my finger in the chaincase and try to manually move over the shift fork and it’s tight it eventually gives way and I can move it freely, reassemble everything and run it , code goes away sled goes in and out of reverse fine, tested 3 times all good, go drive it 30 feet and it won’t go into reverse again SD-08 so I start thinking it’s the actuator maybe just not strong enough, I swap out the one from my dads 2017 tcat, same part number and same result. As soon as I am on the machine and moved 20 feet it won’t go into reverse. Now I’m not sure if I ever fixed the problem from last year or if it’s something to do with the new belt? Also just installed a dalton black orange (updated) in the secondary at 6-2,

sorry for the length of this post I just about tried everything I can think of

also this is what my reverse knob looks like after it fails to go in

 

[WinderFab]

Wouldn’t be the dalton spring, I have the same one on my sled. Do you have another belt to check it with ? If belt is to tight it will cause issues with going into reverse.

 

[JerryBones]

Wouldn’t be the dalton spring, I have the same one on my sled. Do you have another belt to check it with ? If belt is to tight it will cause issues with going into reverse.

I thought about this but this belt was sitting so high in the secondary I assumed if anything it was too long? Even after removing those deflection shins it’s better but still above the secondary. Maybe I’ll throw the 8jp on and try it

 

[hellflyer]

It shouldn't sit above the secondary. This means deflection is to tight and would cause this issue.what ever material you remove from the back of secondary you have to remove from bolt spacer ,weather it's shims or material of the aluminum tube to keep deflection right

 

[THEPASMAN]

I’ve had similar issues on and off. Pretty sure it has to do with belt deflection and/or chain tension. Or a combination of both The jack shaft has to have the right amount of play to mesh the Gears

 

[fourload]

Get the track in the air and see if track spins at idle when belt is warm. If it does it is too tight. Take out shims till the track stops spinning. Also did you cut your aluminum spacer when you machined your clutch? If not you won’t be able to adjust deflection correctly. It needs to be cut the same amount.

 

[74Nitro]

I agree with others, lower the belt more. If the reverse fails to complete the shift within a certain time, it will throw the code. If that gear(s) has enough load due to belt to tight, the servo motor can't overcome it.

 

[JerryBones]

It shouldn't sit above the secondary. This means deflection is to tight and would cause this issue.what ever material you remove from the back of secondary you have to remove from bolt spacer ,weather it's shims or material of the aluminum tube to keep deflection right

makes sense. So the two thin washers on the secondary bolt that I removed were not enough because the circlip and washer on the jack shaft were thicker. I didn’t try machining the aluminum tube I will do that. Sounds like I should shave an extra mm or so off so that I can use those thin washers and have some Room for adjustment down the road.

now would it be a terrible idea to put the circlip back on and put the offset slightly over 59? I think with that circlip back on it would probably fix my deflection issue

 

[JerryBones]

Get the track in the air and see if track spins at idle when belt is warm. If it does it is too tight. Take out shims till the track stops spinning. Also did you cut your aluminum spacer when you machined your clutch? If not you won’t be able to adjust deflection correctly. It needs to be cut the same amount.

I didn’t machine the secondary only removed the washer and circlip behind it and then removed the 2 washers off the bolt but they are much thinner than the washer and circlip. It makes sense thanks for all the help folks I’ll find a way to machine that aluminum plug 2-3mm

 

[fourload]

I didn’t machine the secondary only removed the washer and circlip behind it and then removed the 2 washers off the bolt but they are much thinner than the washer and circlip. It makes sense thanks for all the help folks I’ll find a way to machine that aluminum plug 2-3mm

Yes, you have no adjustment left. It will be very tight till you can get the adjustment back. Machining or taking out washer and circlip will have the same effect. The washer is 1mm and the circlip is 1.5 mm I believe.

 

[JerryBones]

Thanks guys! I added the circlip back on behind the secondary and that corrected my belt deflection and now it goes in and out of reverse, this is only a temporary solution until I can get the aluminum plug machineD down but I’m glad it was an easy fix. Thanks again for the quick responses fellas!

 

[Bigblue1]

I have belt adjuster and machined as well. I found the xs825 is slightly wider than 8jp and likes to sit just
Below the sleeve edge basically at the low er end of factory spec. Went all season last year with no issues.

 

[JerryBones]

I have belt adjuster and machined as well. I found the xs825 is slightly wider than 8jp and likes to sit just
Below the sleeve edge basically at the low er end of factory spec. Went all season last year with no issues.

Yeah once I added the circlip back on the belt dropped to about 1/16” below the top of the secondary and everything works as it should. Hard to believe 1mm caused my problem