savage whoa's ,what to look for ??

[racin_38]

ok today i took my onroad and my savy up to my sons for a little tuning and a nitro fix ,i ran the savy for alittle and my son was having trouble with my car so i took over the controls of the car and he ripped the savy around ,well for some reason i lost the rear drive to it .
there wasn't any grinding or noise he just said he noticed it was spinning the front tires and not the rears ,
what or where do i look first?
diff?
tranny?
i just got it all together and all the new stuff installed and jus tneed a finger pointing me i nthe right direction what to look at
thanx guys
rick

 

[Candyman]

FWD only? OK. Check the outdrive cup from the tranny to see if perhaps you forgot to install the keeper screw, or perhaps it backed out while he was riunning it. Also check the outdrive to the rear diff to see if that has happened there. Then check the outdrive cups on the rear dogbones. And lastly check the rear diff. I expect that if you did the 4-spider mod you should be ok. But if not, there have been a number of cases of blown diffs and that may be the culprit.

 

[savage18SS]

Same exact thing happened to me. If you havent done your spider mod I highly recommend checking your diff. That was my problem

 

[racin_38]

ok i just got done tearing it done after inspecting the hole truck and the rear diff felt like it was slipping 1 time move anotehr time not .
tore it down and thought WTF it blew the spiders and the outdirve gears ,and yes i have the 4 gear mod in it
WHY?
I wasn't doing ungodly jumps or anything liek that just running thru grass and a few wheelies and stuff
should i shim the diff?
and if so what kit do i get ?
i know the maxx you use ofna's 10044 if memory serves me correctly ,

 

[olds97_lss]

What 4 spider mod did you use? The HPI one or a conglomeration of kyosho pins and savage spider gears?

The reason I ask is because the HPI upgrade comes with 3x18mm machine thread screws for the cup. The stock course threaded screws have a tendency to back out in a short time which will cause your spider gears to eat each other up in a short while.

Did you notice if your cup screws had backed out any on you? it would only take a turn or two to give enough slop to toast the diff.

Also, what lube did you use in the diff?

 

[Mugen MTX-2]

I just did the 4 diff mod front and rear, but (stupidly) used Kyosho bevel gears and my SH 28 destroyed both diffs...and I mean DESTROYED...truck was free reving without going anywhere. Only got half a tank out of them.

Did you use the HPI bevel gears? I've just ordered some from Tower now.

 

[racin_38]

i honestly couldnt tell you what mod the guy did ,but i do know he bought them from hpi ,BUT the cup is using a course threaded screw soi guess i will order the new cups and screws
are they any upgraded cups ?aluminum that kinda thing then i can use thread locker i dont want ot have to do this all the time ,
and btw the screwes where tight

oh yeah i am using kyosho 5000 diff oil

 

[olds97_lss]

Maximizer makes them out of 7075, GH makes them, but I think out of 6061, so does FLM (fast lane machine), but I believe theirs are also out of 6061. GPM makes them as well.

I haven't had a problem since I started using machine screws. I also tap the threads with a tap before screwing the machine screw in. Feels like it holds better that way.

maximizer: https://www.ssl-stormerhobbies.com/cgi-bin/seekpart.pl?src=ns&pn=MPI2350
FLM: https://www.ssl-stormerhobbies.com/cgi-bin/seekpart.pl?src=ns&pn=FLM44000
GH: http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHCA4&P=ML

Forgot about Nova: http://www.novarcproducts.com/savagediffcup.html
There's are probably the best bang for the buck. 7075 aluminum (hard stuff) for $22 a piece.

 

[racin_38]

thanx olds i will add that to my christmas list lol