Author Topic: Downshifting going down hill  (Read 7710 times)

Offline 1980c10

  • Senior Member
  • ****
  • Posts: 1205
Re: Downshifting going down hill
« Reply #15 on: May 25, 2011, 11:58:19 PM »
Its all about backpressure and rpms.

Online VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 19038
Re: Downshifting going down hill
« Reply #16 on: May 26, 2011, 01:19:35 PM »
No Engine braking in second:
Front servo or accumulator oil rings may be leaking.
Front band may be broken or burned out.
Front band not engaged on anchor pin and/or servo pin.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline bigchevyc30

  • Frequent Member
  • **
  • Posts: 456
  • the pig
Re: Downshifting going down hill
« Reply #17 on: May 27, 2011, 06:32:39 AM »
well in the owners manual i had for my truck it showed that i can only go 45 in L1 and L2 and i can shift into the L ranges above 50 it wont go in until i hit 45 so as not to ruin the tranny also a cool thing i learned of my FF rear axle idk what type it is its a 1ton axle but until i get over 15 mph its a full pos rear end then switchs to regular after i get to 15 and ive proven that it works. i know i must be blowing some peoples minds right now
idk i have a TH400 and it doesnt have the 1st or 2nd gear it just has the complete gears to change the ratio for like pulling a big load up a hill. it has L1 and L2 so i cant down shift

What?  ???

This has got to be good. LOL
1980 c-30 dually R.I.P
1989 R2500 Sub 350/sm465
1984 k10 sub 6.2/700r4

Offline 1979C20

  • Senior Member
  • ****
  • Posts: 1659
  • Kyle Taulton.
Re: Downshifting going down hill
« Reply #18 on: May 27, 2011, 03:45:42 PM »
That posi is called a gov locker. Ive got one in the rear of my 2 wheel drive, and it can hang with the jeeps offroad(mostly). Supposedly theyre known to grenade. And mine unlocks closer to 20, and it seems ad if it locks up when theres too much load on one tire, like a limited slip.
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline screamin86

  • Junior Member
  • ***
  • Posts: 661
Re: Downshifting going down hill
« Reply #19 on: May 27, 2011, 04:13:52 PM »
Yeah its a gov-loc or know as the gov-bomb. They work but if you look at one closely you or atleast I couldn't understand how they would hold up. I blew one up in the rearend of my 03 yukon xl. I've always had issues with them unlocking and locking randomly too.
86 k10 lwb 4x4:350 .040 214/224 444/466 112lsa performer rpm 1406 lt's summit racing th350 2800stall
03 yukon xl:tint debadge full boltons
86 ta:lm7 hot cam boltons

Offline malibu795

  • Frequent Member
  • **
  • Posts: 336
Re: Downshifting going down hill
« Reply #20 on: May 28, 2011, 10:35:58 PM »
No Engine braking in second:
Front servo or accumulator oil rings may be leaking.
Front band may be broken or burned out.
Front band not engaged on anchor pin and/or servo pin.
i was about to pull out hte ATSG..


whats with the back pressure/rpm stuff???????? i can get a downshift skid when i had a 350 and 400s...

floating?????????? itsd fluid coupling.. and yes you acn shut the engine off and it will windmill down the road if your at speed.
adam wildman
75 K25 383/400
79 malibu 454/T56 305rwhp/432rwtq 15.6@92.8mph
02 2500HD D-max/allison best time 13.77 @ 99mph 463rwhp/930rwtq