Community
Search
Notices
HPI Monster Truck Forum Talk about HPI monster trucks here. The infamous Savage 21, SS, .25 or any other HPI MT. You can optionally discuss HPI in our general MT discussion forum if you prefer.

Diff failing, or other?

Thread Tools
 
Search this Thread
 
Old 10-08-2010, 03:47 PM
  #1  
Shenanigans
Senior Member
Thread Starter
My Feedback: (12)
 
Join Date: Nov 2009
Location: Kansas City, MO
Posts: 657
Likes: 0
Received 0 Likes on 0 Posts
Default Diff failing, or other?

Ihave recently noticed I get considerable "torque steer", or what Ibelieve to be it.....on hard accelleration my savy pulls to the left until Ihit top speed and it straightens out. Its fairly easily controlled with my tx, but Im curious if this is a sign my diffs are failing, or just a bald tire linkage issue? It seems to have started once my lrp 30 got to about the gallon mark and started waking up and putting out some power, and has slowly gotten worse every outing. Ido not run BPdiffs at this time, and probably wont until these fail. They are not shimmed either. My Phaltlines have lost much of their tread, but still have the grooves......however I doubt they grip much. Ihave ext tvp's and xl width.

This was my first nitro truck, so Im a little green on the warning signs diffs are failing except the obvious complete failure. Just curious if Ineed to be looking to replace any other parts before they do go and I get the BP's.....or run it into the ground and be confident the BP's will straighten everything out. Thanks in advance
Old 10-08-2010, 04:30 PM
  #2  
rc person 577
Senior Member
 
rc person 577's Avatar
 
Join Date: Mar 2010
Location: Homer, NY
Posts: 390
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Diff failing, or other?

When you turn one wheel, does the other turn with no odd noises?
Also, check your wheel hexs, make sure they are not rounded on the wheel themselves. That happened to me, and caused a nasty torque steer.
Old 10-08-2010, 04:39 PM
  #3  
Shenanigans
Senior Member
Thread Starter
My Feedback: (12)
 
Join Date: Nov 2009
Location: Kansas City, MO
Posts: 657
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Diff failing, or other?

havent checked my hexes....but will.  Wheels turn smooth, no noise.
Old 10-09-2010, 11:10 AM
  #4  
PrjctStrtFrce
Senior Member
My Feedback: (10)
 
PrjctStrtFrce's Avatar
 
Join Date: Aug 2005
Location: Bartlett, IL
Posts: 2,948
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Diff failing, or other?

Could just be the result of those tires. I put those on for kicks without adjusting any of my gearing/shift points, and the thing just spun like crazy and went sideways. Also, check to make sure that your servo saver set-up is good and tight as well. Do you have good steering otherwise?
Old 10-09-2010, 02:02 PM
  #5  
Argess
 
Argess's Avatar
 
Join Date: Jan 2006
Location: Pleasantville, NS, CANADA
Posts: 2,358
Likes: 0
Received 4 Likes on 4 Posts
Default RE: Diff failing, or other?

I think all RC differentials will exhibit a little of that behaviour. Mind you, I'm not sure, but I think most of mine do. I don't notice it off-road, but when on asphalt, it's apparent.

You could try filling the diffs with thick silicone oil if you only have grease in there now. It will help with cornering too. I forget just now what the recommended oil weights are, but I"m sure somebody can chime in with a good recommendation.
Old 10-09-2010, 03:34 PM
  #6  
Shenanigans
Senior Member
Thread Starter
My Feedback: (12)
 
Join Date: Nov 2009
Location: Kansas City, MO
Posts: 657
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Diff failing, or other?

Im thinking you are right....tires in combination with asphalt running is making it push a little bit...I run 50k in the front and rear as it is now....Im due for a fresh set of tires, so Ill see how it acts after I mount em. 

prjc- I have fair steering for xl width, and a hitec 645mg steering servo...could be a lot better, but turns ok while moving.  Bought one of those cheapo 244 oz servos off the marketplace here and have been running it in my truggy for throttle and has been flawless so far.  May give it a test in a savage for steering...cant beat the price if it performs good.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.