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Mickey Richaud
Mickey Richaud
Townsend TN
(114 posts)

Registered:
08/25/2015 06:36AM

Main British Car:
'69 BGT GM 3.4

T5 5th Gear "Rattle"
Posted by: Mickey Richaud
Date: February 06, 2018 07:37PM

Folks: I've read that T5's can be noisy, especially in 5th. The World Class T5 in my GT has had a rattle in 5th since I installed it. Consequently I had it rebuilt by Stan at Pro-Force Performance in Georgia (nice guy, and came recommended), as it had other issues; but it is still noisy in 5th under load under 50 mph, and sometimes in 4th around same rpm (though not nearly as loud). Once it gets up to speed it's quiet, but kinda bothersome otherwise. With the 3.9 rear end, I'm often at a speed where 4th gear the engine rpm runs a bit high for comfort/economy, and 5th gear too low (rattles).

I'm running Pennzoil Synchromesh fluid, per Stan's recommendation. Anything better out there, or is that the fluid of choice?

Hope this makes sense! And thanks for any input.

Mickey


mgb260
Jim Nichols
Sequim,WA
(1843 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: T5 5th Gear "Rattle"
Posted by: mgb260
Date: February 06, 2018 08:42PM

Mickey, I think Synchromesh oil is the best. I would check transmission mount and U joints. Could also be the snap ring that keeps the gears in place came loose.



Edited 2 time(s). Last edit at 02/07/2018 03:34AM by mgb260.


Mickey Richaud
Mickey Richaud
Townsend TN
(114 posts)

Registered:
08/25/2015 06:36AM

Main British Car:
'69 BGT GM 3.4

Re: T5 5th Gear "Rattle"
Posted by: Mickey Richaud
Date: February 07, 2018 06:27AM

Thanks, Jim.

I emailed Stan, and he said the rear cluster shaft bearing might need a thicker shim. I've asked him if this is something I can live with, or if it has to be addressed to avoid failure. The adventure continues!


Mickey Richaud
Mickey Richaud
Townsend TN
(114 posts)

Registered:
08/25/2015 06:36AM

Main British Car:
'69 BGT GM 3.4

Re: T5 5th Gear "Rattle"
Posted by: Mickey Richaud
Date: February 07, 2018 08:01AM

If it were the snap ring, would it not make noise in all gears? Same with mounts and u-joints? The noise is really only in fifth and very rarely in fourth, both under load/lugging situation.


MGBV8
Carl Floyd
Kingsport, TN
(3273 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: MGBV8
Date: February 07, 2018 10:01AM

Wrong stuff, Mickey.

Synchromesh is for Non-World Class T-5 transmissions with brass synchros.

World Class T-5 transmissions all use ATF. The composite fiber lined synchros do not do as well with Synchromesh.

Mobil 1 ATF (synthetic) come highly recommended. I have been using Valvoline synthetic ATF for many years now.

Loose countershaft bearing is a good possibility.

Stop lugging the engine. ;)


IaTR6
Dennis Costello
Central Iowa
(121 posts)

Registered:
12/29/2007 02:53PM

Main British Car:
'73 TR 6

Re: T5 5th Gear "Rattle"
Posted by: IaTR6
Date: February 07, 2018 11:32AM

So, Pro-Force says it may need to have the counter gear shimmed? Shouldn't that have been done at the time of the rebuild?
I have had two "rebuilt" transmissions, both advertised as "heavy duty", when in fact they were both standard 265 ft lb rated.
The first had an interior case that looked like an old crankcase it was so dirty. The second, had the 5th-reverse pivot bolt removed, and
reinstalled finger tight without sealant on the threads. Watch the video by Paul Cangliosi (sp?) at 5speeds.com.
Dennis


mgb260
Jim Nichols
Sequim,WA
(1843 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: T5 5th Gear "Rattle"
Posted by: mgb260
Date: February 07, 2018 03:20PM

Carl, You are right on fluid recommendation but a lot of guys have switched to Synchromesh in the WC T5 instead of ATF and have smoother shifting and more durability. The older NWC T5 was supposed to use 70-90 WT G4 and has brass synchros. Synchromesh is formulated for newer transmissions and will work with both kinds of synchros.



Mickey Richaud
Mickey Richaud
Townsend TN
(114 posts)

Registered:
08/25/2015 06:36AM

Main British Car:
'69 BGT GM 3.4

Re: T5 5th Gear "Rattle"
Posted by: Mickey Richaud
Date: February 07, 2018 04:14PM

I put Synchromesh in it, based on research I'd done and Stan's recommendation. In an email this morning, Stan said he's now recommending Mobile 1 Synthetic. Suggested I drain it and see how the fluid looks, and then switch to the Mobile 1. That's the plan for now.

Stan also checked his notes on the rebuild and found that he replaced my "large fifth gear and bearings"; he then wondered if it could be the yoke or the driveshaft. Since I've had the noise from the beginning, it may well be one of those.

Thanks for the input. Keep it coming!


MGBV8
Carl Floyd
Kingsport, TN
(3273 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: MGBV8
Date: February 08, 2018 01:02PM

Hold the phone!
Quote:
I think it is "generally held" on internet forums or from people who for the most part, do not know the history or have worked on T5's since 1982. Yes 1982. My company did warranty work for GM in the early 1980's.
All non wc boxs both from FORD and GM took Dextron II. In fact I need to find some early GM NWC cases that came from the factory with orange USE DEXTRON II stickers on them and stick a picture on web to cut out this nonsense. The only NWC transmission that used gear lube was the Jeep unit.

The Jeep units where plagued with burn out issues because of this.

People don't realize that the T5 shaft to gear clearances and pilot shaft sections have fairly tight clearances. They were designed to use the lighter weight oil to get into those tight voids. Prior to the T5 the T50 used ATF as well.

Using gear lube in a NWT5 or WC is a bad thing not an improvement. You have to ask yourself what is the advantage? Some people think the thick oil protects things better, yet fail to realize shifting is effected, cooling and oil flow within the transmission are drastically reduced.

since Dexron-II is no longer manufactured, the best alternative to use is Mobil 1 multi purpose ATF or Royal Purple Synchromax. Both have worked fine for me. We use exclusively only the Royal Purple Synchromax.

Paul Cangialosi
www.5speeds.com Creators of the JT5 5 speed!

[www.allfordmustangs.com]

Quote:
Borg Warner (and Tremec after they purchased BW in 2008) specifically stated in their service manual that NWC was not to be serviced with gear oil, and that you should refer to the vehicle manufacturer for fluid recommendation. Ford specially stated in their owner guides and service manuals that Dexron II was the fluid to be used for NCW.
Stan Peace or Pro-Force Performance.com (an SEFB sponsor) and I went back and forth on this subject at AFM back in late 2009.

[www.allfordmustangs.com]

Be sure to read the response from Paul Cangialosi (of www.5speeds.com) on page 2 of that thread.

And Stan's post about the whole gear oil myth on SEFB: [sefb.net]

Modern Driveline had for years (until early 2011) stated that NWC used 70wt gear oil. No mention of Dexron II or any other ATF whatsoever. That was wrong then and is wrong now.

Stan's website on the T-5 history states this about fluid for the NWC:

[www.pro-forceperformance.com]

Transmission Fluid

BorgWarner allowed each manufacturer to choose the lubricant for its particular application, but it seems that BorgWarner's recommendation was Dexron-II ATF from the very beginning. GM adopted the Dexron, as proven by the stickers placed on each transmission. Ford adopted Dexron as their official fluid, as proven by specifying the ATF product in their original 1983 and 1984 Field Service Manual publications. For some reason, AMC chose to continue specifying gear oil instead of ATF. The early style of Dexron is no longer available. Generic ATF such as DEX/MERC is a suitable substitute. A Ford dealer will recommend their Mercon-V ATF which is also a good substitute.

Many Internet sources insist that gear oil should be used in the Non-World Class T-5, but the documentation above clearly reveals that both Ford and GM chose to use ATF from the start. Using gear oil in a Non-World Class transmission will not significantly damage the transmission, but many times, due to Internet confusion as to what is, and is not, a World Class T-5, gear oil has been mistakenly used in the World Class units.


Update on Dexron VS Gear oil for NON-World Class T-5's:

Dexron-III ATF replaced Dexron-II in 1993. While Dexron-III meets or exceeds the previous specifications, the viscocity of Dexron-III is thinner than the original Dexron-II that was specified for the NON-World Class T-5. This thinner fluid is fine for the World Class T-5 with the lined synchro rings, but the NON-World Class T-5 with the brass synchro rings needs a thicker fluid to work optimally. As a result, Tremec has specified 30W MOTOR OIL for the NON-World Class T-5's. While Tremec has not published an official document about this, it is confirmed by an email dated 1/9/2012 from a Tremec Engineering/Support employee.

[vb.foureyedpride.com]


Mickey Richaud
Mickey Richaud
Townsend TN
(114 posts)

Registered:
08/25/2015 06:36AM

Main British Car:
'69 BGT GM 3.4

Re: T5 5th Gear "Rattle"
Posted by: Mickey Richaud
Date: February 08, 2018 01:22PM

Carl -

Care to translate? Not sure where that's taking me. Mobil 1 or Synchromesh or Dexron III or Royal Purple Synchromax? Any real difference?


MGBV8
Carl Floyd
Kingsport, TN
(3273 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: MGBV8
Date: February 08, 2018 03:02PM

Biggest takeaway for me was Ford & GM always used ATF in their T-5 trannies. Dexron II (ATF that is NLA) was specified for NWC. I did not know that.

Use the Mobil 1 synthetic, Mickey. Then, try to find your noise.


mgb260
Jim Nichols
Sequim,WA
(1843 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: T5 5th Gear "Rattle"
Posted by: mgb260
Date: February 08, 2018 03:41PM

Carl, Being a Jeep Guy is probably where I got my info. The old Dexron was thicker, around 20WT. Synchromesh is similar to 30WTin viscosity. I have run it in NWC and have heard many recommendations for the WC T5. It is expensive though. How much is a QT of Mobile 1 ATF?



Edited 1 time(s). Last edit at 02/09/2018 10:22AM by mgb260.


MGBV8
Carl Floyd
Kingsport, TN
(3273 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: MGBV8
Date: February 09, 2018 09:14AM

Good question. Will have to do some price shopping. I buy my motor oil at Wally World.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5389 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: BlownMGB-V8
Date: February 09, 2018 11:17AM

Mobil 1 is almost as expensive as Synchromesh, but not quite. My early(ish) TKO came with documents recommending Synchromesh, so let's just add that to the confusion. I felt like it should have been a little quicker on the shifts but I'm not sure if that means Dextron-III or Mobil 1 would be better or not.

Jim


Charles
Charles Long
McDonald, TN
(156 posts)

Registered:
09/15/2013 08:54AM

Main British Car:
1966 MGB V6 1994 Camaro 3.4L 60V6

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: Charles
Date: February 13, 2018 07:48PM

Mickey, if it helps the fluid that was in my T5 is red. I know cause it drips on a white towel when we get home. I plan to fix the leak but I will need to use a BFH on the car body to make clearance to tighten the drain plug.

Get some ear plugs or go deaf like me and carry go. Carry AAA card, a cell, and credit card, and a few adult beverages for the wait on AAA.

Regards
charles



Mickey Richaud
Mickey Richaud
Townsend TN
(114 posts)

Registered:
08/25/2015 06:36AM

Main British Car:
'69 BGT GM 3.4

Re: T5 5th Gear "Rattle"
Posted by: Mickey Richaud
Date: February 13, 2018 08:00PM

Thanks, Charles - knew I could depend on you! :-)


MGBV8
Carl Floyd
Kingsport, TN
(3273 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: T5 5th Gear "Rattle"
Posted by: MGBV8
Date: February 14, 2018 10:02AM

If I would dare park my B on a towel, it had better be black. ;)


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