Rebuilt T5 Grinding into 4th - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Rebuilt T5 Grinding into 4th

Coil Spring Options from Ruffstuff!Flush Mount LED Bumper Lights, CREEThe Original 3/8" Ruffstuff Diff Cover!

Reply
Unread 10-02-2013, 08:27 AM   #1
Grims
Registered User
1983 CJ7 
 
Join Date: Jan 2008
Location: Houston, TX
Posts: 337
Rebuilt T5 Grinding into 4th

I recently purchased a CJ with a rebuilt T5 that's about a month old (he gave me the receipts) Shortly after taking ownership it would start grinding on the shift into 4th, pretty aggressively so. After it cools down it will then work fine again for about 10 miles. I can get it to shift smoothly into 4th if I take a 2 second or so pause in neutral on the way down, then it will pop in 4th without issues.

The only troubleshooting step I have made so far is to drain the fluid. I filled it back up with Royal Purple ATF, but it hasn't made a difference. I have read a few threads that Pennzoil Syncromesh can resolve these types of issues...but I haven't been able to find it anywhere.

I see there is a pretty big debate on what the proper fluid is for these things, and it seems like each camp claims the other will destroy the tranny. It can be rather confusing.

I do have a couple quarts of Royal Purple 75-90 in the garage I could try if anyone thinks it has a chance of changing anything.

Grims is offline   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:14 AM   #2
MoneypitCJ5
Registered User
1977 CJ5 
 
Join Date: Mar 2013
Location: Florence, AL
Posts: 170
Gear oil of any weight is not a good idea in a T5. Its not designed to work with that heavy a fluid.

The synchromesh should be fine...it is the recommended fluid for T56 and several other manual transmissions. I'm tempted to try it in my Challenger, as I have read quite a bit about it having better shift characteristics than using ATF.

It might help with your fourth gear shift problem, but if it does, feel lucky. It sounds like you have a synchro trying to go out.
__________________
1973 VW Karmann-Ghia first car
2009 Challenger R/T 6MT, Flowmaster, inTune daily driver
1977 CJ5 304, 3MT - under construction
And many in between!
MoneypitCJ5 is offline   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:16 AM   #3
Grims
Registered User
1983 CJ7 
 
Join Date: Jan 2008
Location: Houston, TX
Posts: 337
Yeh it feels like a syncro issue, but if it was wouldn't 2nd gear be acting up too? I'm not going to argue the gear oil in the T5, but apparently it was recommended at one time to use in it, and many on the forums seem to swear by it.
Grims is offline   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:28 AM   #4
keith460
Jeep. There's Only One
 
keith460's Avatar
1984 CJ7 
 
Join Date: Jan 2007
Location: Doylestown, PA
Posts: 5,020
I'd recommend either the Pennzoil or Royal Purple synchromesh gear oils. Both can be bought at NAPA or AutoZone.

I have used it for years in both my original T4 and now T5 transmissions. Shifting is smooth as well as downshifting and it is compatible with these transmissions bronze clocking rings.

You may be having issues with the clocking ring for the fourth gear.

Sent from my iPhone using JeepForum
__________________
.
1984 CJ-7 Renegade
__________________

Restoration Thread:http://www.jeepsunlimited.com/forums...d.php?t=434226
keith460 is online now   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:28 AM   #5
MoneypitCJ5
Registered User
1977 CJ5 
 
Join Date: Mar 2013
Location: Florence, AL
Posts: 170
My experience with T5's is limited to 5.0 Mustangs. Of course in a Mustang its usually 2nd or 3rd gear that goes out first, due to missed shifts while speed shifting...

2nd 3rd 4th and 5th all have individual synchros so its possible to lose one and everything else work just fine. I drove my Mustang with absolutely no third gear for awhile and you'd never know there was a problem.

As for the question of fluid, I know there's always a ton of debate about it. I know synchromesh is great fluid from personal experience.
__________________
1973 VW Karmann-Ghia first car
2009 Challenger R/T 6MT, Flowmaster, inTune daily driver
1977 CJ5 304, 3MT - under construction
And many in between!
MoneypitCJ5 is offline   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:32 AM   #6
Grims
Registered User
1983 CJ7 
 
Join Date: Jan 2008
Location: Houston, TX
Posts: 337
So does anyone think draining 30 dollars worth of Royal Purple ATF out of it and putting in syncromesh will make a difference? I went to an Auto Zone, and two advanced autos and neither had synchromesh. I'll do some calls today and find a store that does.
Grims is offline   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:38 AM   #7
jdarg
Registered User
2006 LJ Wrangler 
 
Join Date: Jan 2004
Posts: 625
It won't. Put that $30 towards opening the trans back up and fixing the real problem.

Usually the lower gear synchros are the ones that start grinding first. A fourth gear grind is not normal at all, esp. if 2-3 don't do it, esp. if it was just rebuilt. There is no fix in a bottle here, where a minor 1-2 or 2-3 grind can actually sometimes be made SLIGHTLY better or worse, esp. in the cold temps, w/ different fluids.

Pennz synchromesh has worked better for me than RP in the applications I've tried it in (nv3550, nsg370).RPs marketing/distribution is superior to many of its products. A lot of their products have poorer specs than most (if not all) competitors products.
__________________
'94 YJ - SBC/AX15/231, SOA, 8.8, 34" swampers
'06 LJ Rubicon - 31" ATs, OME 2.5", belly-up skid, other junk
'75 CJ5 - 232/T14/D20, 'glass tub w/ 2" BL, otherwise stock
jdarg is offline   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:39 AM   #8
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 10,964
Grims,

When my SR4's (the predecessor to the T4) 4th gear started to grind, switching to synchromesh didn't help.

You can probably avoid any addition damage by double clutching, which should buy you a little more time, but I'm afraid you will have to crack that baby open and fix it, eventually.

Matt
Matt1981CJ7 is online now   Reply With Quote Quick reply to this message
Unread 10-02-2013, 09:40 AM   #9
Grims
Registered User
1983 CJ7 
 
Join Date: Jan 2008
Location: Houston, TX
Posts: 337
It is freshly rebuilt...so it sounds like something was put back together wrong. Is replacing a syncro very hard, does it take any special tools?
Grims is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.